Table Of Contents
Cisco IOS In-Service Software Upgrade Process
Prerequisites for Performing ISSU
Restrictions for Performing ISSU
Information About Performing ISSU
Redundant LC ISSU Process Overview
Versioning Capability in Cisco IOS Software to Support ISSU
ISSU-Capable Protocols and Applications
Restrictions for ISSU-Capable Protocols and Applications With ISSU-uBR10K
ISSU Single-Step Upgrade Process
How to Perform the RP ISSU Process
Restrictions for Performing the RP ISSU Process
ISSU Multi-Step Upgrade Process
Loading Cisco IOS Software on the Standby RP
Stopping the RP ISSU Rollback Timer
Verifying the RP ISSU Software Installation
ISSU Single-Step Upgrade Process
Aborting a Software Upgrade Using ISSU
Configuring the Rollback Timer to Safeguard Against Upgrades
Displaying ISSU Compatibility Matrix Information
How to Perform the Redundant LC ISSU Process
Prerequisites for Performing the Redundant LC ISSU Process
Restrictions for Performing the Redundant LC ISSU Process
Running the RLC ISSU Process Automatically
Stopping the Automatic RLC ISSU Process
Running the RLC ISSU Process Manually
Manually Switching the Primary Working Cable Line Card to Standby
Manually Loading the New Image on the Primary Line Card in Standby
Manually Switching to the Standby Cable Line Card
Accepting the RLC ISSU Process
Verifying the RLC ISSU Software Installation
Forcing the RLC ISSU Process to Run
Manually Rolling Back a Software Upgrade Using RLC ISSU
Reloading Non-Redundant Cable Line Cards
Stopping a Manual RLC ISSU Process
Restarting a Stopped RLC ISSU Process
Configuration Examples for Performing ISSU
Verifying Redundancy Mode Before Beginning the ISSU Process: Example
Verifying the ISSU State: Example
Performing the RP ISSU Process: Example
Initiating the RP ISSU Process: Example
Forcing a Switchover from the Active RP to the Standby RP: Example
Stopping the RP Rollback Process: Example
Committing the New Software to the Standby RP: Example
Aborting the RP ISSU Process: Example
Verifying RP Rollback Timer Information: Example
Verifying the ISSU Single Step Upgrade: Example
Configuration Examples for Performing RLC ISSU
Configuration Examples for the Automatic RLC ISSU Process
Initiating the RLC ISSU Process for all Cable Line Cards: Example
Initiating the RLC ISSU Process for Specific Cable Line Cards: Example
Stopping the Automatic RLC ISSU Process: Example
Forcing an Automatic RLC ISSU Process: Example
Configuration Examples for the Manual RLC Process
Performing the RLC ISSU Process Manually: Example
Manually Rolling Back a Software Upgrade Using RLC ISSU: Example
Reloading Non-Redundant Cable Line Cards: Example
Stopping a Manual RLC ISSU Process: Example
Cisco IOS In-Service Software Upgrade Process
First Published: December 17, 2008Last Updated: November 29, 2010The In-Service Software Upgrade (ISSU) process allows Cisco IOS software to be updated or otherwise modified while packet forwarding continues. In most networks, planned software upgrades are a significant cause of downtime. ISSU allows Cisco IOS software to be modified while packet forwarding continues, which increases network availability and reduces downtime caused by planned software upgrades. This document provides information about ISSU concepts and describes the steps taken to perform ISSU in a system.
Finding Feature Information
Your software release may not support all the features documented in this module. For the latest feature information and caveats, see the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the "Feature Information for ISSU" section.
Use Cisco Feature Navigator to find information about platform support and Cisco IOS, Catalyst OS, and Cisco IOS XE software image support. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.
Contents
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Prerequisites for Performing ISSU
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Prerequisites for Performing ISSU
General Prerequisites
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Table 1 shows the hardware compatibility prerequisites for this feature.
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Table 1 ISSU Hardware Compatibility Matrix
Cisco uBR10012 Universal Broadband Router
Cisco IOS Release 12.2(33)SCA and later
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Cisco IOS Release 12.2(33)SCB and later
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Cisco IOS Release 12.2(33)SCA and later
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Cisco IOS Release 12.2(33)SCC and later
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Cisco IOS Release 12.2(33)SCE and later
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1 Cisco uBR3GX60V cable interface line card is not compatible with PRE2. You must use PRE4 with the Cisco uBR3GX60V cable interface line card.
Cisco uBR10012 Universal Broadband Router Platform Prerequisites
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For more information about configuring N+1 redundancy, see N+1 Redundancy for the Cisco CMTS Routers.
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Please see "MDR Support for ISSU" section for more details.
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The following commands are used to check the PRE processor module CPU utilization and line card CPU utilization respectively prior to start of the ISSU process:
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Restrictions for Performing ISSU
General Restrictions
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Cisco uBR10012 Universal Broadband Router Platform Restrictions
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Information About Performing ISSU
Before you perform ISSU, you should understand the following concepts:
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ISSU-uBR10K Process Overview
The ISSU-uBR10K feature enhances the set of High Availability (HA) features on the Cisco uBR10012 Universal Broadband Router by providing software upgrade or downgrade services for Cisco IOS software images and line card images on redundant Cisco uBR10012 router hardware, with minimal interruption of service. ISSU-uBR10K includes RP ISSU support between Performance Routing Engines and MDR support for certain WAN line cards, and extends the ISSU process to cable line cards.
On the Cisco uBR10012 router, the ISSU-uBR10K process consists of two phases:
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If a cable line card is not configured for N+1 line card redundancy, you need to upgrade via a sequential reload, using the issu linecard reloadversion command.This will cause interruption of data service for the cable line card.
Switchovers during both the RP and RLC ISSU processes ensure that there are no cable modem drops (CMs do not go offline) and no PacketCable voice call drops.
RP ISSU Process Overview
The RP ISSU process allows you to perform a Cisco IOS software upgrade or downgrade while the system continues to forward packets. Cisco IOS ISSU takes advantage of the Cisco IOS high availability infrastructure—Cisco NSF with SSO and hardware redundancy—and eliminates downtime associated with software upgrades or version changes by allowing changes while the system remains in service (see Figure 1). Cisco IOS software high availability features combine to lower the impact that planned maintenance activities have on network service availability, with the results of less downtime and better access to critical systems.
SSO mode supports configuration synchronization. When images on the active and standby RPs are different, this feature allows the two RPs to be kept in synchronization although they may support different sets of commands.
Figure 1 High Availability Features and Hardware Redundancy in the ISSU Process
An ISSU-capable router consists of two RPs (active and standby) and one or more line cards. Before initiating the ISSU process, copy the Cisco IOS software into the file systems of both RPs (see Figure 2).
Figure 2 How to Load New Cisco IOS Software on Both RPs
After you have copied the Cisco IOS software to both file systems, load the new version of Cisco IOS software onto the standby RP (see Figure 3).
Figure 3 Load New Cisco IOS Software on the Standby RP
After switchover, the standby RP takes over as the new active RP (see Figure 4).
Figure 4 Switch Over to Standby RP
Then, the former active RP, which is now the new standby RP, is loaded with the new software (see Figure 5).
Figure 5 Load New Standby RP with New Cisco IOS Software
The two RPs in a system can be in one of three different states during ISSU:
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Figure 6 shows the ISSU states during the ISSU process.
Figure 6 ISSU States During the ISSU Process
Stateful Switchover Overview
Development of the SSO feature is an incremental step within an overall program to improve the availability of networks constructed with Cisco IOS routers.
In specific Cisco networking devices that support dual RPs, SSO takes advantage of RP redundancy to increase network availability by establishing one of the RPs as the active processor while the other RP is designated as the standby processor, and then synchronizing critical state information between them. Following an initial synchronization between the two processors, SSO dynamically maintains RP state information between them.
A switchover from the active to the standby processor occurs when the active RP fails, is removed from the networking device, or is manually taken down for maintenance.
Cisco NSF is used with SSO. Cisco NSF allows for the forwarding of data packets to continue along known routes while the routing protocol information is being restored following a switchover. With Cisco NSF, peer networking devices do not experience routing flaps, thereby reducing loss of service outages for customers.
Figure 7 illustrates how SSO is typically deployed in service provider networks. In this example, Cisco NSF with SSO is enabled at the access layer (edge) of the service provider network. A fault at this point could result in loss of service for enterprise customers requiring access to the service provider network.
For Cisco NSF protocols that require neighboring devices to participate in Cisco NSF, Cisco NSF-aware software images must be installed on those neighboring distribution layer devices. Depending on your objectives, you may decide to deploy Cisco NSF and SSO features at the core layer of your network. Doing this can help reduce the time to restore network capacity and service for certain failures, which leads to additional availability.
Figure 7 Cisco NSF with SSO Network Deployment: Service Provider Networks
Additional levels of availability may be gained by deploying Cisco NSF with SSO at other points in the network where a single point of failure exists. Figure 8 illustrates an optional deployment strategy that applies Cisco NSF with SSO at the enterprise network access layer. In this example, each access point in the enterprise network represents another single point of failure in the network design. In the event of a switchover or a planned software upgrade, enterprise customer sessions would continue uninterrupted through the network.
Figure 8 Cisco NSF with SSO Network Deployment: Enterprise Networks
For further information on SSO, see the Stateful Switchover document.
NSF Overview
Cisco NSF works with the SSO feature in Cisco IOS software. SSO is a prerequisite of Cisco NSF. NSF works with SSO to minimize the amount of time a network is unavailable to its users following a switchover. The main objective of Cisco NSF is to continue forwarding IP packets following an RP switchover.
Usually, when a networking device restarts, all routing peers of that device detect that the device went down and then came back up. This transition results in what is called a routing flap, which could spread across multiple routing domains. Routing flaps caused by routing restarts create routing instabilities, which are detrimental to the overall network performance. Cisco NSF helps to suppress routing flaps in SSO-enabled devices, thus reducing network instability.
Cisco NSF allows for the forwarding of data packets to continue along known routes while the routing protocol information is being restored following a switchover. With Cisco NSF, peer networking devices do not experience routing flaps. Data traffic is forwarded through intelligent line cards or dual forwarding processors (FPs) while the standby RP assumes control from the failed active RP during a switchover. The ability of line cards and FPs to remain up through a switchover and to be kept current with the Forwarding Information Base (FIB) on the active RP is key to Cisco NSF operation.
Redundant LC ISSU Process Overview
The redundant LC (RLC) ISSU process is introduced in Cisco IOS Release 12.2(5th)SB on the Cisco uBR10012 Universal Broadband Router to support software upgrades without service interruption on supported, redundantly-configured cable line cards. The RLC ISSU process is the second phase of ISSU support in the ISSU-uBR10K feature and is supported only on the Cisco uBR10-MC5X20S/U/H cable line cards on the Cisco uBR10012 router. The dual TCC+ or DTCC+ cards are sequentially reloaded after running the issu runversion command.
The RLC ISSU process has some dependencies with the RP ISSU process. First, the RLC ISSU process can be started only when the RP ISSU process reaches the Run Version (RV) state. In the RV state, the RP rollback timer is stopped (via the issu acceptversion command) and the active RP is running the new version of the software image. Each of the cable line cards have reconnected to the new RP and ISSU image negotiation has occurred between the RP and the cable line cards (Figure 9).
Figure 9 RP ISSU Process Stages With WAN Line Card MDR
At this point in the RP ISSU process, the stages of the RLC ISSU process can be executed. The stages of the RLC ISSU process are comparable to the stages that occur in the RP ISSU process. The RLC ISSU process itself can be initiated to run manually or automatically. In the manual method, the Prepare Version (only in RLC ISSU process), Load Version, Run Version, and Accept Version stages are executed in step-by-step fashion by running the corresponding issu linecard command for each stage of the process. In the automatic method, a single command (issu linecard changeversion) is executed to run each of these stages back-to-back and automatically as each stage completes (Figure 10).
Figure 10 RLC ISSU Process Stages
The RLC ISSU process runs serially for each targeted cable line card. A subsequent cable line card may start the process when the previous cable line card's RLC ISSU process is complete. This process is different from the ISSU process for other line cards supporting MDR, which reloads simultaneously during the Run Version stage of the RP ISSU process.
Finally, when the RLC ISSU process is complete for all redundant cable line cards, a condition is set such that the RP ISSU Commit Version stage can be executed. The RP and RLC ISSU processes share the Commit Version stage such that the issu commitversion command confirms both the RP and RLC images at the same time (Figure 11).
Figure 11 Combined RP and RLC ISSU Commit Version Stage
While the RLC ISSU process also supports the functions of aborting a version upgrade as the RP ISSU process does, it has the additional functions of stopping an automatic RLC ISSU process, stopping other RLC ISSU processes in the middle of execution, and reloading a version. The Reload Version function is intended to support cable line cards that are not configured for redundancy and that do not support the MDR function of the RP ISSU process.
Figure 12 provides a graphical overview of these RP and RLC ISSU processes.
Figure 12 RP and RLC ISSU Process Summary View
Versioning Capability in Cisco IOS Software to Support ISSU
Before the introduction of the ISSU capability, the SSO mode of operation required each RP to be running like versions of Cisco IOS software. The operating mode of the system in a redundant HA configuration is determined by exchanging version strings when the standby RP registers with the active RP.
The system entered SSO mode only if the versions running on the both RPs were the same. If not, the redundancy mode was reduced to ensure compatibility. With ISSU capability, the implementation allows two different but compatible release levels of Cisco IOS images to interoperate in SSO mode and enables software upgrades while packet forwarding continues. Version checking done before ISSU capability was introduced is no longer sufficient to allow the system to determine the operating mode.
ISSU requires additional information to determine compatibility between software versions. Therefore, a compatibility matrix is defined that contains information about other images with respect to the one in question. This compatibility matrix represents the compatibility of two software versions, one running on the active and the other on the standby RP, and to allow the system to determine the highest operating mode it can achieve. Incompatible versions will not be able to progress to SSO operational mode.
The Cisco IOS infrastructure has been internally modified and redesigned to accommodate subsystem versioning with ISSU. Cisco IOS subsystems correspond to feature sets and software component groupings. Features or subsystems that maintain state information across RPs are HA-aware or SSO clients. A mechanism called ISSU Framework, or ISSU protocol, allows subsystems within Cisco IOS software to communicate RP to RP and to negotiate the message version for communication between RPs. Internally, all NSF- and SSO-compliant applications or subsystems that are HA-aware must follow this protocol to establish communication with their peer across different versions of software. (For further information on operating modes, see the Stateful Switchover document.)
Compatibility Matrix
You can perform the ISSU process when the Cisco IOS software on both the active and the standby RP is capable of ISSU and the old and new images are compatible. The compatibility matrix information stores the compatibility among releases as follows:
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The compatibility matrix represents the compatibility relationship a Cisco IOS software image has with all of the other Cisco IOS software versions within the designated support window (for example, all of those software versions the image "knows" about) and is populated and released with every image. The matrix stores compatibility information between its own release and prior releases. It is always the newest release that contains the latest information about compatibility with existing releases in the field. The compatibility matrix is available within the Cisco IOS software image and on Cisco.com so that users can determine in advance whether an upgrade can be done using the ISSU process.
Before attempting an ISSU, you should determine the compatibility level between the Cisco IOS software versions on the active and the standby RPs. To display the compatibility matrix data between two software versions on a given system, enter the show issu comp-matrix negotiated command.
Compatibility Information for ISSU-uBR10K on the Cisco uBR10012 Universal Broadband Router
The show issu comp-matrix negotiated command provides information about the compatibility for the Cisco IOS software images on the active and standby PRE-2 cards. Compatibility information between the RP images and LC images, or LC to LC images is not explicitly reported in this output.
However, if the show issu comp-matrix negotiated command indicates compatibility between RP images, then RP to LC, and LC to LC image compatibility is also supported.
The following example shows sample output from the show issu comp-matrix negotiated command on the Cisco uBR10012 Universal Broadband Router:
Router# show issu comp-matrix negotiatedCardType: uBR10000(107), Uid: 2, Image Ver: 12.2(20070219:204203)145Image Name: UBR10K2-K9P6U2-MCid Eid Sid pSid pUid Compatibility=======================================================2 1 65538 65542 15 COMPATIBLE2 1 65543 65542 11 COMPATIBLE2 1 65549 65543 17 COMPATIBLE2 1 65579 4 1 COMPATIBLE3 1 65577 6 1 COMPATIBLE4 1 65567 13 1 COMPATIBLE5 1 65547 27 1 COMPATIBLE7 1 65570 5 1 COMPATIBLE8 1 65572 11 1 COMPATIBLE9 1 65540 0 2 COMPATIBLE9 1 65541 0 2 COMPATIBLE9 1 65545 0 2 COMPATIBLE9 1 65563 0 2 COMPATIBLE9 1 65569 2 1 COMPATIBLE9 1 65573 0 2 COMPATIBLE9 1 65575 0 2 COMPATIBLE10 1 60 0 2 COMPATIBLEISSU-Capable Protocols and Applications
The following protocols and applications support ISSU:
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Restrictions for ISSU-Capable Protocols and Applications With ISSU-uBR10K
The following protocols and applications are not supported with ISSU-uBR10K:
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SNMP Support for ISSU
ISSU - SNMP for SSO provides a mechanism for synchronizing the SNMP configurations and the MIBs that support SSO from the active RP to the standby RP, assuming that both RPs are running the same version of Cisco IOS software. This assumption is not valid for ISSU.
ISSU - SNMP provides an SNMP client that can handle ISSU transformations for the MIBs. An SNMP client (SIC) handles ISSU for all MIBs and handles the transmit and receive functions required for ISSU. During SNMP, a MIB is completely synchronized from the active RP to the standby RP only if the versions of the MIB on both Cisco IOS releases are the same.
MDR Support for ISSU
Minimum Disruptive Restart (MDR) is a feature that allows line cards to be restarted to minimize the disruption of traffic passing through the system. It prevents line protocol flaps and minimizes traffic disruption across a restart or reload of software. The uBR10K platform supports MDR of the Cisco 10000-SIP-600 jacket card and the SPA-24XDS-SFP (Wideband DOCSIS SPA). ISSU prevents network outage whenever the 10000-SIP-600 card or the Wideband SPA card reloads.
The advantages of the MDR feature in ISSU are:
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MDR and FPGA Upgrade
Most often when performing MDR ISSU upgrade for the Cisco 10000-SIP-600 jacket card and the SPA-24XDS-SFP, only the firmware is upgraded - the FPGA will remain intact. However, there might be some rare cases where the FPGA will need to be upgraded. In these cases, the MDR ISSU process will become FPGA upgrade process. Unlike MDR ISSU, FPGA Upgrade will cause all traffic passing through the Cisco 10000-SIP-600 jacket card to be completely disrupted. During this FPGA upgrade process, the new FPGA will be downloaded to each SPA. It takes approximately 12 minutes to download the new FPGA to each SPA.
The FPGA upgrade process is an independent process from the system ISSU process. The system ISSU process triggers the FPGA upgrade process during the issu runversion step, and will continue to upgrade other cable line cards in the system. These two processes execute at the same time, and one process can finish before the other.
The show upgrade fpd progress command can be used to check the status of the FPGA upgrade process.
ISSU Single-Step Upgrade Process
Single-step upgrade process is the ability of the ISSU feature to upgrade the entire CMTS system using the issu changeversion command. This process allows the corresponding networking device to inform the system that the networking device is performing a complete upgrade cycle automatically, and the state transitions to move to the next step automatically.
The ISSU upgrade process consists of three states:
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Each of these states is defined by a set of variables, that is, primary version (PV), secondary version (SV), current version (CV), and ISSU state (IS). The transition of all these states is accomplished using the issu changeversion command, which automatically performs these state transitions.
Figure 13 provides a graphical overview of the single-step upgrade process.
Figure 13 Single-step Upgrade Process Summary View
The advantages of the Single-Step Upgrade process are:
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How to Perform the RP ISSU Process
Unlike SSO, which is a mode of operation for the device and a prerequisite for performing RP ISSU, the ISSU process is a series of steps performed while the router or switch is in operation. The steps result in the implementation of new or modified Cisco IOS software, and have a minimal impact to traffic.
Restrictions for Performing the RP ISSU Process
The following list provides basic restrictions for performing the RP ISSU process:
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Restrictions for Performing the RP ISSU Process on the Cisco uBR10012 Universal Broadband Router
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The tasks in the following sections explain how to complete the ISSU process:
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ISSU Multi-Step Upgrade Process
The ISSU multi-step upgrade process consists of the following tasks:
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Loading Cisco IOS Software on the Standby RP
This task describes how to use ISSU to load a new Cisco IOS software to the standby RP.
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SUMMARY STEPS
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Switching to the Standby RP
This task describes how to switch to the standby RP, which is running the new Cisco IOS software image.
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Stopping the RP ISSU Rollback Timer
The following task describes how to stop the rollback timer. If the rollback timer is not stopped, the system automatically aborts the RP ISSU process and reverts to the original Cisco IOS software version if the next RP ISSU procedure is not performed prior to the rollback timer timeout. For example, the RP ISSU process would abort after the issu acceptversion command was entered only if the issu runversion command was not entered before rollback timeout.
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Verifying the RP ISSU Software Installation
During the RP ISSU process, there are three valid states: init, load version, and run version. Use the show issu state command to get information on each or all of these states:
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You can verify the ISSU software installation by entering show commands that provide information on the state of the during the ISSU process.
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ISSU Single-Step Upgrade Process
You can upgrade the entire CMTS system by issuing the issu changeversion command. This command executes individual ISSU phases in the correct sequence automatically, and reduces the human effort involved in executing the other ISSU commands. The issu changeversion command upgrades the router processors first and then upgrades the line cards.
When the issu changeversion command is issued, it executes the functionality of the issu loadversion, issu runversion, issu acceptversion, issu linecard changeversion all and issu commitversion commands, without any user intervention required to navigate through each step of the single-step upgrade process.
The single-step upgrade process involves the following steps:
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Aborting a Software Upgrade Using ISSU
You can abort the ISSU process at any stage manually by issuing the issu abortversion command. The ISSU process also aborts on its own if the software detects a failure.
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If you abort the process after you issue the issu loadversion command, then the standby RP is reset and reloaded with the original software.
If the process is aborted after either the issu runversion or issu acceptversion command is entered, then a second switchover is performed to the new standby RP that is still running the original software version. The RP that had been running the new software is reset and reloaded with the original software version.
This task describes how to abort the ISSU process before a user has committed to the process by issuing the issu commitversion command.
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Configuring the Rollback Timer to Safeguard Against Upgrades
The Cisco IOS software maintains an ISSU rollback timer. The rollback timer provides a safeguard against an upgrade that may leave the new active RP in a state in which communication with the RP is severed.
A user may want to configure the rollback timer to fewer than 45 minutes (the default) so that the user need not wait in case the new software is not committed or the connection to the router was lost while it was in runversion mode. A user may want to configure the rollback timer to more than 45 minutes in order to have enough time to verify the operation of the new Cisco IOS software before committing the new image.
Once you are satisfied that the ISSU process has been successful and you want to remain in the current state, you must indicate acceptance by issuing the issu acceptversion command, which stops the rollback timer. Therefore, entering the issu acceptversion command is extremely important to moving the ISSU process forward.
Issuing the issu commitversion command at this stage is equal to entering both the issu acceptversion and the issu commitversion commands. Use the issu commitversion command if you do not intend to run in the current state for a period of time and are satisfied with the new software version.
This task explains how to configure the rollback timer.
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Displaying ISSU Compatibility Matrix Information
The ISSU compatibility matrix contains information about other software images about the version in question. This compatibility matrix represents the compatibility of the two software versions, one running on the active and the other on the standby RP, and the matrix allows the system to determine the highest operating mode it can achieve. This information helps the user identify whether or not to use ISSU.
This task explains how to display information about the ISSU compatibility matrix.
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How to Perform the Redundant LC ISSU Process
Just as with RP ISSU, the RLC ISSU process is a series of steps performed while the router is in operation. The steps result in the implementation of a new or modified software image on a cable line card, and have minimal impact to traffic. The RLC ISSU process can be run automatically for certain cable line cards or globally for all cable line cards, or you can run the process manually for individual cable line cards.
Prerequisites for Performing the Redundant LC ISSU Process
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For more information about configuring N+1 redundancy, refer to the "N+1 Redundancy for the Cisco Cable Modem Termination System" chapter of the Cisco CMTS Feature Guide at:
http://www.cisco.com/en/US/docs/cable/cmts/feature/guide/uFGnpls1.html
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Router(config)# config-register 0x2–
Router(config)# boot system disk0:ubr10k2-k9p6u2-mz.new•
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Once you verify that the active RP is in Run Version (RV state) after using the issu acceptversion command, you can begin the RLC ISSU process.
Restrictions for Performing the Redundant LC ISSU Process
The following list describes the restrictions for performing the RLC ISSU process:
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If a working line card fails during this period while the protect line card is unavailable, the working line card will reload with the software image that corresponds to the currently active RP. N+1 synchronization between the working and protect line cards is maintained.
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The timeout values for the Cisco uBR10012 router are:
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The tasks in the following sections explain how to perform the RLC ISSU process:
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Running the RLC ISSU Process Automatically
When you run the RLC ISSU process automatically using the issu linecard changeversion command, you can specify running the process for all redundant cable line cards, or for specified working cable line cards.
If you want to force the RLC ISSU process regardless of the image version status, or you want to ignore any potential service outage and error handling, use the issu linecard changeversion forced form of the command.
You can also use the issu linecard changeversion command to restart the RLC ISSU process if you previously used the issu linecard process stop command.
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Once the automatic RLC ISSU process is complete, you need to verify the installation and commit the RP and LC images. The following sections describe these tasks:
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Stopping the Automatic RLC ISSU Process
You can stop the automatic RLC ISSU process if you want to interrupt the process from continuing for the next cable line card that is configured for RLC ISSU.
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Running the RLC ISSU Process Manually
The tasks in the following sections explain how to perform the RLC ISSU process manually:
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Once you accept the RLC ISSU process, you can begin the manual RLC ISSU process for another cable line card. If you have completed the RLC ISSU process, then you need to verify the installation and commit the RP and LC images. The following sections describe these tasks:
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The following sections explain optional tasks that you can perform as part of the manual RLC ISSU process:
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Manually Switching the Primary Working Cable Line Card to Standby
To begin the RLC ISSU process manually, use the issu linecard prepareversion command and specify the slot/subslot location of the primary working cable line card. When you enter this command, the redundant configuration and image version of the cable line card are checked. If the image version needs to be changed, then a switchover occurs placing the primary working cable line card in standby mode, and activating the protect cable line card.
If you want to force the switchover regardless of the image version status, or you want to ignore any potential service outage and error handling, use the issu linecard prepareversion forced form of the command.
You can also use the issu linecard prepareversion command to restart the RLC ISSU process if you previously used the issu linecard process stop command.
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DETAILED STEPS
Manually Loading the New Image on the Primary Line Card in Standby
To load the new target line card image on the specified working cable line card that is currently in standby mode as part of the manual RLC ISSU process, use the issu linecard loadversion command.
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Manually Switching to the Standby Cable Line Card
To initiate an N+1 switchover to the current standby cable line card (the original working primary cable line card) as part of the manual RLC ISSU process, use the issu linecard runversion command. During this stage, the primary working cable line card becomes active (with the new target image) for all of the interfaces on the secondary protect cable line card. A 3-second rollback timer for the primary working cable line card is started.
If you want to force the switchover regardless of any image version incompatibility, or you want to ignore any potential service outage and error handling, use the issu linecard runversion forced form of the command.
SUMMARY STEPS
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DETAILED STEPS
Accepting the RLC ISSU Process
To mark completion of and accept the Prepare Version, Load Version, and Run Version stages of the RLC ISSU process, use the issu linecard acceptversion command.
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Verifying the RLC ISSU Software Installation
During the RLC ISSU process, there are many different valid states. Use the show issu linecard state command display these line card states:
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You can also use some other show commands to display the status of the N+1 redundancy configuration and the status of the RP ISSU process.
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Forcing the RLC ISSU Process to Run
You can configure the automatic RLC ISSU process, or certain stages of the manual RLC ISSU process to continue processing regardless of any potential service outage and subsequent error handling, by using the forced keyword option on the corresponding commands.
For more information, see the following topics:
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Manually Rolling Back a Software Upgrade Using RLC ISSU
If you determine that the system running the new software image does not function as expected, you can configure the RLC ISSU process to roll back all cable line cards, or certain cable line cards to the previous version using the issu linecard abortversion command.
If you want to force the abort process and ignore any potential service outage and error handling, use the issu linecard abortversion forced form of the command.
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SUMMARY STEPS
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Reloading Non-Redundant Cable Line Cards
To load a new target line card image on a cable line card that is not configured redundantly, use the issu linecard reloadversion command.
Caution
SUMMARY STEPS
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Stopping a Manual RLC ISSU Process
To manually stop any RLC ISSU operation, use the issu linecard process stop command.
SUMMARY STEPS
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DETAILED STEPS
Restarting a Stopped RLC ISSU Process
If you have previously stopped an RLC ISSU operation using the issu linecard process stop command, you can restart the process using either the issu linecard changeversion or issu linecard prepareversion commands.
The RLC ISSU process will restart at the next logical ISSU operation to be performed depending on the current state of the system.
For more information about how to use these commands, see the "Running the RLC ISSU Process Automatically" section or the "Manually Switching the Primary Working Cable Line Card to Standby" section.
Finishing the ISSU Process to Enable the New Cisco IOS Software Version on the RP and Cable Line Cards
After loading new Cisco IOS software to the standby RP, causing the standby RP to become the active RP and the former active RP to become the standby RP, you need to enable the new standby RP to use the new Cisco IOS software version. This task explains how to perform that process.
Beginning in Cisco IOS Release 12.2(5th)SB on the Cisco uBR10012 Universal Broadband Router, the issu commitversion command is used to confirm both the new RP and new LC images that were upgraded using the RLC ISSU process (See Figure 11).
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Configuration Examples for Performing ISSU
This section contains the following configuration examples:
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Verifying Redundancy Mode Before Beginning the ISSU Process: Example
Before you begin the ISSU process, verify the redundancy mode for the system. NSF and SSO must be configured before attempting an ISSU. The following example displays verification that the system is in SSO mode and that slot A—RP A is the active R, and slot B—RP B is the standby RP. Both RPs are running the same Cisco IOS software image.
Router# show redundancy statesmy state = 13 -ACTIVEpeer state = 8 -STANDBY HOTMode = DuplexUnit = PrimaryUnit ID = 0Redundancy Mode (Operational) = SSORedundancy Mode (Configured) = SSORedundancy State = SSOMaintenance Mode = DisabledManual Swact = enabledCommunications = Upclient count = 45client_notification_TMR = 30000 millisecondsRF debug mask = 0x0Router# show redundancyRedundant System Information :------------------------------Available system uptime = 18 minutesSwitchovers system experienced = 0Standby failures = 0Last switchover reason = noneHardware Mode = DuplexConfigured Redundancy Mode = SSOOperating Redundancy Mode = SSOMaintenance Mode = DisabledCommunications = UpCurrent Processor Information :-------------------------------Active Location = slot ACurrent Software state = ACTIVEUptime in current state = 17 minutesImage Version = Cisco IOS Software, 10000 Software (UBR10K2-K9P6U2-M), Version 12.2(nightly.BEMR070507) NIGHTLY BUILD, synced to mayflower NIGHTLY_MAYFLOWER_041607_0143Copyright (c) 1986-2007 by Cisco Systems, Inc.Compiled Tue 08-May-07 01:23 by toroweBOOT = bootflash:ubr10k2-k9p6u2-mz.old,12;CONFIG_FILE =BOOTLDR =Configuration register = 0x2Peer Processor Information :----------------------------Standby Location = slot BCurrent Software state = STANDBY HOTUptime in current state = 16 minutesImage Version = Cisco IOS Software, 10000 Software (UBR10K2-K9P6U2-M), Version 12.2(nightly.BEMR070507) NIGHTLY BUILD, synced to mayflower NIGHTLY_MAYFLOWER_041607_0143Copyright (c) 1986-2007 by Cisco Systems, Inc.Compiled Tue 08-May-07 01:23 by toroweBOOT = bootflash:ubr10k2-k9p6u2-mz.old,12;CONFIG_FILE =BOOTLDR =Configuration register = 0x2Verifying the ISSU State: Example
The following example provides information about the ISSU state:
Router# show issu state detailSlot = ARP State = ActiveISSU State = InitBoot Variable = disk0:ubr10k4-k9p6u2-mz.122SC_20100329,12;Operating Mode = SSOPrimary Version = N/ASecondary Version = N/ACurrent Version = disk0:ubr10k4-k9p6u2-mz.122SC_20100329Variable Store = PrstVblSlot = BRP State = StandbyISSU State = InitBoot Variable = disk0:ubr10k4-k9p6u2-mz.122SC_20100329,12;Operating Mode = SSOPrimary Version = N/ASecondary Version = N/ACurrent Version = disk0:ubr10k4-k9p6u2-mz.122SC_20100329Slot Red Role Peer Act/Sby Image Match RP LC ISSU State ISSU Proc---- --------- ---- -------- -------------- ------------------ ---------5/0 Secondary - standby Yes - -6/0 Primary 5/0 active Yes - -7/0 Primary 5/0 active Yes - -8/0 Primary 5/0 active Yes - -PRE is the new active: FALSEWaiting for MDR: FALSENo Transitional Line Card State information registered.No Peer Line Card State information registered.Peer Line Card Action:-------Card Type-------- -----Action------ --Slots---24rfchannel-spa-1 NO ACTION 0x000000044jacket-1 NO ACTION 0x000000042cable-dtcc NO ACTION 0x000000281gigethernet-hh-1 NO ACTION 0x00000200The new version of the Cisco IOS software must be present on both of the RPs. The initial bootflash directory examples show the presence of the old image, and the disk0 directory information shows that the new version is present on both disks.
Directory of bootflash:/1 -rw- 2530312 Jan 1 2000 01:42:10 +00:00 c10k2-eboot-mz.122-16.BX2 -rw- 35530056 May 9 2007 17:11:42 +00:00 ubr10k2-k9p6u2-mz.oldDirectory of stby-bootflash:/1 -rw- 2530312 Jan 1 2000 01:42:10 +00:00 c10k2-eboot-mz.122-16.BX2 -rw- 35530056 May 9 2007 17:11:42 +00:00 ubr10k2-k9p6u2-mz.oldDirectory of disk0:/1 -rw- 35530056 May 9 2007 17:11:42 +00:00 ubr10k2-k9p6u2-mz.newDirectory of stby-disk0:/1 -rw- 35530056 May 9 2007 17:11:42 +00:00 ubr10k2-k9p6u2-mz.newPerforming the RP ISSU Process: Example
The following examples explain how to verify the ISSU software installation by entering show commands that provide information on the state of the during the ISSU process.
Initiating the RP ISSU Process: Example
To initiate the ISSU process, enter the issu loadversion command as shown in the following example:
Router# issu loadversion a disk0:ubr10k2-k9p6u2-mz.new b stby-disk0:ubr10k2-k9p6u2-mz.newThe following two examples display the ISSU state and redundancy state after ISSU process initiation:
Router# show issu stateSlot = ARP State = ActiveISSU State = Load VersionBoot Variable = bootflash:ubr10k2-k9p6u2-mz.old,12;Slot = BRP State = StandbyISSU State = Load VersionBoot Variable = disk0:ubr10k2-k9p6u2-mz.new,12;bootflash:ubr10k2-k9p6u2-mz.old,12;Router# show redundancy statemy state = 13 -ACTIVEpeer state = 8 -STANDBY HOTMode = DuplexUnit = PrimaryUnit ID = 0Redundancy Mode (Operational) = SSORedundancy Mode (Configured) = SSOSplit Mode = DisabledManual Swact = EnabledCommunications = Upclient count = 31client_notification_TMR = 30000 millisecondsRF debug mask = 0x0Forcing a Switchover from the Active RP to the Standby RP: Example
At this point, the system is ready to switch over and run the new version of Cisco IOS software that has been loaded onto the standby RP. When you enter the issu runversion command, an SSO switchover will be performed, and NSF procedures will be invoked if so configured.
Router# issu runversion b stby-disk0:ubr10k2-k9p6u2-mz.newOnce the ISSU process has been completed, the system will be running the new version of software and the previously active RP will now become the standby RP. The standby will be reset and reloaded, but it will remain on the previous version of software and come back online in STANDBY-HOT status. The following example shows how to connect to the newly active RP and verify these conditions.
Router# show redundancyRedundant System Information :------------------------------Available system uptime = 24 minutesSwitchovers system experienced = 1Standby failures = 0Last switchover reason = user initiatedHardware Mode = DuplexConfigured Redundancy Mode = SSOOperating Redundancy Mode = SSOMaintenance Mode = DisabledCommunications = UpCurrent Processor Information :-------------------------------Active Location = slot BCurrent Software state = ACTIVEUptime in current state = 8 minutesImage Version = Cisco IOS Software, 10000 Software (UBR10K2-K9P6U2-M), Version 12.2(nightly.BEMR070507) NIGHTLY BUILD, synced to mayflower NIGHTLY_MAYFLOWER_041607_0143Copyright (c) 1986-2007 by Cisco Systems, Inc.Compiled Tue 08-May-07 01:23 by toroweBOOT = disk0:ubr10k2-k9p6u2-mz.new,12;bootflash:ubr10k2-k9p6u2-mz.old,12;CONFIG_FILE =BOOTLDR =Configuration register = 0x2Peer Processor Information :----------------------------Standby Location = slot ACurrent Software state = STANDBY HOTUptime in current state = 6 minutesImage Version = Cisco IOS Software, 10000 Software (UBR10K2-K9P6U2-M), Version 12.2(nightly.BEMR070507) NIGHTLY BUILD, synced to mayflower NIGHTLY_MAYFLOWER_041607_0143Copyright (c) 1986-2007 by Cisco Systems, Inc.Compiled Tue 08-May-07 01:23 by toroweBOOT = bootflash:ubr10k2-k9p6u2-mz.old,12;CONFIG_FILE =BOOTLDR =Configuration register = 0x2Router# show issu stateSlot = BRP State = ActiveISSU State = Run VersionBoot Variable = disk0:ubr10k2-k9p6u2-mz.new,12;bootflash:ubr10k2-k9p6u2-mz.old,12;Slot = ARP State = StandbyISSU State = Run VersionBoot Variable = bootflash:ubr10k2-k9p6u2-mz.old,12;The new active RP is now running the new version of software, and the standby RP is running the old version of software and is in the STANDBY-HOT state.
Stopping the RP Rollback Process: Example
In the following example, the "Automatic Rollback Time" information indicates the amount of time left before an automatic rollback will occur. Enter the issu acceptversion command within the time period specified by the rollback timer to acknowledge that the RP has achieved connectivity to the outside world; otherwise, the ISSU process is terminated, and the system reverts to the previous version of Cisco IOS software by switching to the standby RP.
Router# show issu rollback-timerRollback Process State = In progressConfigured Rollback Time = 45:00Automatic Rollback Time = 29:03Entering the issu acceptversion command stops the rollback timer:
Router# issu acceptversion b disk0:ubr10k2-k9p6u2-mz.newCommitting the New Software to the Standby RP: Example
The following example shows how to commit the new Cisco IOS software image in the file system of the standby RP and ensure that both the active and the standby RPs are in the run version (RV) state. The standby RP is reset and reloaded with the new Cisco IOS software and returned to STANDBY-HOT status.
Router# issu commitversion a stby-disk0:ubr10k2-k9p6u2-mz.newRouter# show redundancy statesmy state = 13 -ACTIVEpeer state = 8 -STANDBY HOTMode = DuplexUnit = SecondaryUnit ID = 1Redundancy Mode (Operational) = SSORedundancy Mode (Configured) = SSOSplit Mode = DisabledManual Swact = EnabledCommunications = Upclient count = 31client_notification_TMR = 30000 millisecondsRF debug mask = 0x0Router# show redundancyRedundant System Information :------------------------------Available system uptime = 35 minutesSwitchovers system experienced = 1Standby failures = 1Last switchover reason = user initiatedHardware Mode = DuplexConfigured Redundancy Mode = SSOOperating Redundancy Mode = SSOMaintenance Mode = DisabledCommunications = UpCurrent Processor Information :-------------------------------Active Location = slot BCurrent Software state = ACTIVEUptime in current state = 18 minutesImage Version = Cisco IOS Software, 10000 Software (UBR10K2-K9P6U2-M), Version 12.2(nightly.CISCO070530) NIGHTLY BUILD, synced to V122_32_8_23_SBKCopyright (c) 1986-2007 by Cisco Systems, Inc.Compiled Tue 30-May-07 02:02 by toroweBOOT = disk0:ubr10k2-k9p6u2-mz.new,12;CONFIG_FILE =BOOTLDR =Configuration register = 0x2Peer Processor Information :----------------------------Standby Location = slot ACurrent Software state = STANDBY HOTUptime in current state = 4 minutesImage Version = Cisco IOS Software, 10000 Software (UBR10K2-K9P6U2-M), Version 12.2(nightly.CISCO070530) NIGHTLY BUILD, synced to V122_32_8_23_SBKCopyright (c) 1986-2007 by Cisco Systems, Inc.Compiled Tue 30-May-07 02:02 by toroweBOOT = disk0:ubr10k2-k9p6u2-mz.new,12;CONFIG_FILE =BOOTLDR =Configuration register = 0x2Router# show issu stateSlot = BRP State = ActiveISSU State = InitBoot Variable = disk0:ubr10k2-k9p6u2-mz.new,12;disk0:ubr10k2-k9p6u2-mz.new,1;Slot = ARP State = StandbyISSU State = InitBoot Variable = disk0:ubr10k2-k9p6u2-mz.new,12;disk0:ubr10k2-k9p6u2-mz.new,1;Router# show issu state detailSlot = BRP State = ActiveISSU State = InitBoot Variable = disk0:ubr10k2-k9p6u2-mz.new,12;disk0:ubr10k2-k9p6u2-mz.new,1;Operating Mode = SSOPrimary Version = N/ASecondary Version = N/ACurrent Version = disk0:ubr10k2-k9p6u2-mz.newSlot = ARP State = StandbyISSU State = InitBoot Variable = disk0:ubr10k2-k9p6u2-mz.new,12;disk0:ubr10k2-k9p6u2-mz.new,1;Operating Mode = SSOPrimary Version = N/ASecondary Version = N/ACurrent Version = disk0:ubr10k2-k9p6u2-mz.newThe ISSU process has been completed. At this stage, any further Cisco IOS software version upgrade or downgrade will require that a new ISSU process be invoked.
Aborting the RP ISSU Process: Example
The following example shows how to abort the RP ISSU process manually:
Router# issu abortversion b disk0:ubr10k2-k9p6u2-mz.newIf you abort the process after you have entered the issu loadversion command, then the standby RP is reset and is reloaded with the original software version.
Verifying RP Rollback Timer Information: Example
To display rollback timer information for the RP ISSU process, enter the show issu rollback-timer command:
Router# show issu rollback-timerRollback Process State = In progressConfigured Rollback Time = 45:00Automatic Rollback Time = 29:03Verifying the ISSU Single Step Upgrade: Example
The following example provides information about the state and current version of the RPs including the Single Step Upgrade process.
Router# show issu state detailSlot = ARP State = ActiveISSU State = InitBoot Variable = disk0:ubr10k4-k9p6u2-mz.122SC_20100329,12;Operating Mode = SSOPrimary Version = N/ASecondary Version = N/ACurrent Version = disk0:ubr10k4-k9p6u2-mz.122SC_20100329Variable Store = PrstVblSlot = BRP State = StandbyISSU State = InitBoot Variable = disk0:ubr10k4-k9p6u2-mz.122SC_20100329,12;Operating Mode = SSOPrimary Version = N/ASecondary Version = N/ACurrent Version = disk0:ubr10k4-k9p6u2-mz.122SC_20100329Slot Red Role Peer Act/Sby Image Match RP LC ISSU State ISSU Proc---- --------- ---- -------- -------------- ------------------ ---------5/0 Secondary - standby Yes - -6/0 Primary 5/0 active Yes - -7/0 Primary 5/0 active Yes - -8/0 Primary 5/0 active Yes - -PRE is the new active: FALSEWaiting for MDR: FALSENo Transitional Line Card State information registered.No Peer Line Card State information registered.Peer Line Card Action:-------Card Type-------- -----Action------ --Slots---24rfchannel-spa-1 NO ACTION 0x000000044jacket-1 NO ACTION 0x000000042cable-dtcc NO ACTION 0x000000281gigethernet-hh-1 NO ACTION 0x00000200Configuration Examples for Performing RLC ISSU
This section provides configuration examples for the RLC ISSU process. It includes the following sections:
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Configuration Examples for the Automatic RLC ISSU Process
This section provides the following configuration examples:
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Initiating the RLC ISSU Process for all Cable Line Cards: Example
The following example shows how to initiate the RLC ISSU process automatically for all cable line cards in a redundant configuration:
Router> enableRouter# issu linecard changeversion allInitiating the RLC ISSU Process for Specific Cable Line Cards: Example
The following example shows how to initiate the RLC ISSU process automatically for certain working cable line cards in a redundant configuration:
Router> enableRouter# issu linecard changeversion 6/0 6/1 7/1 8/0 8/1Stopping the Automatic RLC ISSU Process: Example
The following example shows how to stop the automatic RLC ISSU process in between the ISSU process for each configured cable line card:
Router# issu linecard changeversion stopForcing an Automatic RLC ISSU Process: Example
The following example shows how to force the automatic RLC ISSU process and ignore any error processing:
Router> enableRouter# issu linecard changeversion 6/0 6/1 7/1 8/0 8/1 forcedor, alternatively:
Router> enableRouter# issu linecard changeversion all forced
Configuration Examples for the Manual RLC Process
Performing the RLC ISSU Process Manually: Example
The following example shows how to run the complete RLC ISSU process manually for a specified working cable line card installed in slot 6 and subslot 0 of the Cisco uBR10012 router:
Router> enableRouter# issu linecard prepareversion 6/0Router# issu linecard loadversion 6/0Router# issu linecard runversion 6/0Router# issu linecard acceptversion 6/0Router# issu commitversion a disk0:ubr10k2-k9p6u2-mz.newManually Rolling Back a Software Upgrade Using RLC ISSU: Example
The following example shows how to manually roll back the line card software image to the original version:
Router# issu linecard abortversion 6/0Reloading Non-Redundant Cable Line Cards: Example
The following example shows how to load a software image for a specific cable line card that is not configured redundantly:
Router# issu linecard reloadversion disk0:ubr10k2-k9p6u2-mz.new 6/0Stopping a Manual RLC ISSU Process: Example
The following example shows how to stop any manual RLC ISSU operation:
Router# issu linecard process stopAdditional References
The following sections provide references related to performing ISSU.
Related Documents
Performing ISSU
Cisco IOS Software: Guide to Performing In-Service Software Upgrades
Information about Cisco Nonstop Forwarding
Cisco Nonstop Forwarding
http://www.cisco.com/en/US/docs/ios/12_2s/feature/guide/fsnsf20s.html
Information about stateful switchover
Stateful Switchover
http://www.cisco.com/en/US/docs/ios/12_2s/feature/guide/fssso20s.html
ISSU and MPLS clients
ISSU MPLS Clients
Information about N+1 line card redundancy
"N+1 Redundancy for the Cisco Cable Modem Termination System" chapter of the Cisco CMTS Feature Guide
http://www.cisco.com/en/US/docs/cable/cmts/feature/guide/uFGnpls1.html
Standards
No new or modified standards are supported by this feature, and support for existing standards has not been modified by this feature.
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MIBs
RFCs
No new or modified RFCs are supported by this feature, and support for existing RFCs has not been modified by this feature.
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Technical Assistance
Feature Information for ISSU
Table 2 lists the features in this module and provides links to specific configuration information. Only features that were introduced or modified in Cisco IOS Release 12.2(33)SCB or a later release appear in the table.
Not all commands may be available in your Cisco IOS software release. For release information about a specific command, see the command reference documentation.
Use Cisco Feature Navigator to find information about platform support and software image support. Cisco Feature Navigator enables you to determine which Cisco IOS, Catalyst OS, and Cisco IOS XE software images support a specific software release, feature set, or platform. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.
Note
Cisco and the Cisco logo are trademarks or registered trademarks of Cisco and/or its affiliates in the U.S. and other countries. To view a list of Cisco trademarks, go to this URL: www.cisco.com/go/trademarks. Third-party trademarks mentioned are the property of their respective owners. The use of the word partner does not imply a partnership relationship between Cisco and any other company. (1110R)
Any Internet Protocol (IP) addresses used in this document are not intended to be actual addresses. Any examples, command display output, and figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses in illustrative content is unintentional and coincidental.
© 2009-2010 Cisco Systems, Inc. All rights reserved.
