Software maintenance upgrade
A software maintenance upgrade (SMU) is a software package that
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is installed on a system to provide a patch or a security fix resolution to a released image, and
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is specific to the corresponding platform.
Feature history
This table provides release and related information about the feature explained in this section.
This feature is also available in all the releases subsequent to the one in which they are introduced in, unless noted otherwise.
|
Feature Name |
Release Information |
Feature Description |
|---|---|---|
|
Software maintenance upgrade |
Cisco IOS XE Gibraltar 16.11.1b |
This feature provides network administrators with targeted, platform-specific patches and security fixes for released images, applicable either on a per-component basis or for the entire corresponding platform. |
A SMU offers significant benefits over classic Cisco IOS software. It lets you address network issues promptly and reduces required testing time and scope. The Cisco IOS XE platform validates SMU compatibility internally and prevents installation of non-compatible SMUs.
All SMUs are also integrated into subsequent Cisco IOS XE software maintenance releases. A SMU is an independent and self-sufficient package without prerequisites or dependencies. You can choose which SMUs to install or uninstall in any order.
![]() Note |
SMUs are supported only on Extended Maintenance releases and throughout the full lifecycle of the underlying software release. |
![]() Note |
Activate the file using the install add file command only from the filesystems of the active device. If you use a file from the standby or member filesystems, the install add file command fails. |
![]() Note |
When the SMU file is deleted and the device is rebooted, the device may display an error message such as:
This error occurs because the previous SMU file was not properly removed from the controller. As a result, you may not be able to install new SMU or APSP files. Use the install remove file command to remove previous instances of APSP or SMU files from the bootflash. |
You can use SMU infrastructure to meet these requirements in wireless contexts:
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Controller SMU: Embedded Wireless Controller bug fixes or Cisco Product Security Incident Response information (PSIRT).
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These fixes or features do not require any changes to the embedded wireless controller.
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APDP: APDP supports new AP models without introducing new hardware or software capabilities.
![]() Note |
The show ap image command displays cumulative statistics for AP images in the controller. Clear the statistics using the clear ap predownload statistics command, before using the show ap image command, to ensure correct data is displayed. |
SMU Workflow
Begin the SMU process by requesting approval from the SMU committee. Contact customer support to raise an SMU request. During the release, the SMU package is posted on the Cisco Software Download page. You can then download and install it.
Warning: Commit changes within six hours of activation or deactivation to avoid rollback
Always run the install commit command within 6 hours after executing either install activate or install deactivate .
If you do not commit changes within this window
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the system automatically reverts to the previous commit state
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this reversion can lead to service interruption, especially over low-bandwidth links where image transfers may not complete in time, and
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remote deployments with slow transfer rates are particularly vulnerable.
To reduce these risks
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run install commit after activation or deactivation
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monitor image transfer progress proactively, and
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plan for available bandwidth and duration at remote sites.
SMU Package
An SMU package contains the metadata and the fix for the reported issue that prompted the request.
SMU Reload
The SMU type describes the effect to a system after installing the SMU. SMUs can be non-traffic affecting or can result in device restart, reload, or switchover.
Controller hot patching support allows SMU to be effective immediately after activation without reloading the system. Other controller SMUs require a cold reload of the system during activation. A cold reload is the complete reload of the operating system.
This action affects the traffic for the duration of the following two phases:
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The reload of the wireless controller.
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The time it takes for all the access points to rejoin the controller, receive the new image from the controller, and upgrade to the new SMU patch. This reload ensures that all processes are started with the correct libraries and files that are installed as part of the SMU.
After the SMU is committed, the activation changes are persistent across reloads.
Overview of Controller SMUs
The following table describes the SMU types supported in the Cisco Embedded Wireless Controller:
|
Package Type |
Use Case |
SMU Type |
Supported on EWC |
|---|---|---|---|
|
Controller SMU - Cold Patch |
Replace impacted binaries, libraries, or subpackages. |
Reload |
Limited support (Patch size < 20 MB). No support for IOSD. |
|
Controller SMU - Hot Patch |
Replace impacted functions. |
Nonreload |
Yes |
|
APSP |
AP fix by replacing the AP image (does not impact the AP running the active controller). |
Nonreload |
Yes |
|
APSP |
AP fix by replacing the AP image (impacts the AP that is running the active controller). |
Reload |
Yes (EWC specific variation) |
|
APDP |
New AP model support without upgrading the controller. |
Nonreload |
Yes |
Managing Controller Hot or Cold SMU Package
Procedure
| Command or Action | Purpose | |
|---|---|---|
|
Step 1 |
install add file tftp: //<server-ip>/<path>/<smu-filename> Example:
|
The |
|
Step 2 |
install activate file backup_image: smu-filename Example:
|
This command is used to activate the patch. The |
|
Step 3 |
install auto-abort-timer stop Example:
|
(Optional) Stops the auto cancel timer in case of activated or deactivated SMUs. |
|
Step 4 |
install commit Example:
|
Commits the activation changes to be persistent across reloads. The commit can be done after activation while the system is up, or after the first reload. If a patch is activated and not committed, the auto cancel timer automatically cancels the activation of the patch in six hours . |
|
Step 5 |
show install rollback Example:
|
Displays the list of rollback IDs that are available. |
|
Step 6 |
install rollback to { base | committed | id | label } specific-rollback-point Example:
|
Rolls back a committed patch. The committed patch can be deactivated and the commit for deactivation can be done using the single install rollback command. |
|
Step 7 |
install deactivate file backup_image: smu-filename Example:
|
install deactivate command causes the reload of the controller in case of a cold patch. There is no reload of the controller in case of a hot
patch.
|
|
Step 8 |
install auto-abort-timer stop Example:
|
(Optional) Stops the auto cancel timer in case of activated or deactivated SMUs. |
|
Step 9 |
install commit Example:
|
Commits the deactivation changes to be persistent across reloads. |
|
Step 10 |
install remove file backup_image: smu-filename Example:
|
|
|
Step 11 |
install abort Example:
|
Cancels the upgrade by resetting the APs in rolling fashion. |
|
Step 12 |
show install summary Example:
|
Displays information about the active package. The output of this command varies based on the packages, and the package states that are installed. |
|
Step 13 |
show install package backup_image: smu-filename Example:
|
Displays information about the SMU package. |
Creating SMU Files (GUI)
Follow the steps given below to create SMU files:
Procedure
|
Step 1 |
Choose Administration > Software Management > Software Maintenance Upgrade (SMU). |
|
Step 2 |
Click Add. |
|
Step 3 |
From the Transport Type drop-down list,
|
|
Step 4 |
Click Add File. |
Configuration Examples for SMU
The following is sample of the SMU configuration:
Device# install add file tftp://10.1.1.2/auto/tftpboot/user1/ewc/ewc-apsp1.bin
install_add: START Tue Jun 4 15:08:26 UTC 2019
Downloading file tftp://10.1.1.2/auto/tftpboot/user1/ewc/ewc-smu.bin
Finished downloading file tftp://10.1.1.2/auto/tftpboot/user1/ewc/ewc-smu.bin to backup_image:ewc-smu.bin
install_add: Adding SMU
install_add: Checking whether new add is allowed ....
install_add: ap image predownload is allowed.
--- Starting initial file syncing ---
Info: Finished copying backup_image: ewc-smu.bin to the selected chassis
Finished initial file syncing
--- Starting SMU Add operation ---
Performing SMU_ADD on all members
[1] SMU_ADD package(s) on chassis 1
MEWLC response success sync_successCumulative SMU Size: 24 KB
Cumulative size of all SMU's will not exceed 20000 KB
Available Memory in /backup_image is 251480 KB
Available memory 251480 KB is greater than available memory required 2000 KB
[1] Finished SMU_ADD on chassis 1
Checking status of SMU_ADD on [1]
SMU_ADD: Passed on [1]
Finished SMU Add operation
SUCCESS: install_add
Device# install activate file backup_image:ewc-apsp1.bin
install_activate: START Tue Jun 4 15:18:58 UTC 2019
install_activate: Activating SMU
Cumulative SMU Size: 24 KB
Cumulative size of all SMU's will not exceed 20000 KB
Available Memory in /backup_image is 250984 KB
Available memory 250984 KB is greater than available memory required 2000 KB
MEWLC response success sync_successExecuting pre scripts....
Executing pre sripts done.
--- Starting SMU Activate operation ---
Performing SMU_ACTIVATE on all members
ls: cannot access '/tmp/sw/fp/*/*/*/mount/.pkginfo': No such file or directory
ls: cannot access '/tmp/sw/fp/*/*/*/mount/.pkginfo': No such file or directory
[1] SMU_ACTIVATE package(s) on chassis 1
valid
install_activate: FP fp error skipping. Platform to fix this in Fru List
[1] Finished SMU_ACTIVATE on chassis 1
Checking status of SMU_ACTIVATE on [1]
SMU_ACTIVATE: Passed on [1]
Finished SMU Activate operation
Executing post scripts....
Executing post scripts done.
Executing post scripts....
Executing post scripts done.
SUCCESS: install_activate /backup_image/ewc-apsp1.bin
Device#install commit
install_commit: START Tue Jun 4 16:15:25 UTC 2019
install_commit: Committing SMU
Executing pre scripts....
install_commit:
Executing pre sripts done.
--- Starting SMU Commit operation ---
Performing SMU_COMMIT on all members
ls: cannot access '/tmp/sw/fp/*/*/*/mount/.pkginfo': No such file or directory
ls: cannot access '/tmp/sw/fp/*/*/*/mount/.pkginfo': No such file or directory
[1] SMU_COMMIT package(s) on chassis 1
valid
[1] Finished SMU_COMMIT on chassis 1
Checking status of SMU_COMMIT on [1]
SMU_COMMIT: Passed on [1]
Finished SMU Commit operation
Waiting for the platform to set the SMU sync timerSMU sync status is sync_successSMU sync to AP's success
/tmp/rp/chasfs/wireless/wlc_notify
SUCCESS: install_commit /backup_image/ewc-apsp1.bin
Device#install rollback to base
install_rollback: START Tue Jun 4 16:42:24 UTC 2019
install_rollback: Rolling back SMU
Executing pre scripts....
install_rollback:
Executing pre sripts done.
--- Starting SMU Rollback operation ---
Performing SMU_ROLLBACK on all members
ls: cannot access '/tmp/sw/fp/*/*/*/mount/.pkginfo': No such file or directory
ls: cannot access '/tmp/sw/fp/*/*/*/mount/.pkginfo': No such file or directory
[1] SMU_ROLLBACK package(s) on chassis 1
[1] Finished SMU_ROLLBACK on chassis 1
Checking status of SMU_ROLLBACK on [1]
SMU_ROLLBACK: Passed on [1]
Finished SMU Rollback operation
Executing post scripts....
Executing post scripts done.
Waiting for the platform to set the SMU sync timerSMU sync status is sync_successSMU sync to AP's success
/tmp/rp/chasfs/wireless/wlc_notifyExecuting post scripts....
Executing post scripts done.
SUCCESS: install_rollback /backup_image/ewc-apsp1.bin Tue Jun 4 16:43:01 UTC 2019
Device# install deactivate file backup_image: ewc-apsp1.bin
install remove file backup_image:ewc-apsp1.bin
Device#show install sum
[ Chassis 1 ] Installed Package(s) Information:
State (St): I - Inactive, U - Activated & Uncommitted,
C - Activated & Committed, D - Deactivated & Uncommitted
--------------------------------------------------------------------------------
Type St Filename/Version
--------------------------------------------------------------------------------
APSP C backup_image:ewc-apsp1.bin
IMG C 17.1.1.0.69043
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Auto abort timer: inactive
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