Table Of Contents
Release Notes for Cisco IOS Release 12.2(10)DA4 for Cisco DSLAMs with NI-2
This release note is Part Number OL-2702-01, Rev. C0, November 1, 2005
These release notes describe features and caveats in Cisco IOS Release 12.2(10)DA4 for the Cisco 6015, Cisco 6160, and Cisco 6260 digital subscriber line access multiplexers (DSLAMs).
Note When you upgrade from Cisco IOS 12.1(5)DA2 or earlier images on the NI-2 card to Release 12.2(10)DA4, you must format the bootflash on the NI-2 card before loading the 12.2(10)DA4 dboot image. See the "Update the Image in Bootflash to the 12.2(10)DA4 dboot Image" section.
For pointers to more information about the Cisco 6015, Cisco 6160, Cisco 6260, and their software, refer to the "Related Documentation" section. To learn more about caveats, visit the Cisco web site—see the "Obtaining Documentation" section for details. Information about electronic documentation can be found in both the "Obtaining Documentation" section and the "Documentation CD-ROM" section.
This document contains the following topics:
Cisco IOS Release 12.2(10)DA4 runs on these DSLAM systems:
New and Changed Information
The following sections provide new and changed information for Cisco IOS Release 12.2(10)DA4, 12.2(10)DA3, 12.2(10)DA2, and 12.2(10)DA.
Cisco IOS Release 12.2(10)DA4
Cisco IOS Release 12.2(10)DA4 is based on Cisco IOS Release 12.2(10)DA3 and includes all of the new features introduced in that release. In addition, this release fixes the bugs described in the "Resolved Caveats—Release 12.2(10)DA4" section.
New Hardware Features in Release 12.2(10)DA4
No new hardware features were introduced in Cisco IOS Release 12.2(10)DA4.
New Software Features in Release 12.2(10)DA
The following new software features were introduced in Cisco IOS Release 12.2(10)DA. No new features were introduced in Release 12.2(10)DA4.
The 8xDMT line card can run in power-management mode in the G.dmt or the T1.413 mode. The resulting power cutback produces a reduction in power dissipation and crosstalk. Only 8xDMT line cards support power management. All CPE may not support the DSL functionality for power management to function correctly. Check with a Cisco customer representative to verify CPE compatibility with the 8xDMT power management.
You control the Power Management feature by issuing a dmt power-management-additional-margin command inside a profile and assigning that profile to a line card interface. This IOS command allows you to set the additional margin for each channel from 0 dB (off) to 15 dB. This sets the additional margin that will be added to the target margin. If the sum of the target margin and additional margin exceeds 15dB, it is capped at 15dB. If the actual margin of the line is higher than the sum of the configured target and additional margin, and all the above conditions are met, then power management attempts to reduce the actual margin, and as a consequence the power level as well.
Not all CPE support power management. If you connect an unsupported CPE to a port on which power management is turned on, you will not see a reduction in the actual margin or power level. The operating modes supported by power management are T1.413and g-992-1 (G.DMT). Table 1 shows the CPE and specifies which operating mode supports them.
A reduction in the power level occurs if there is excess margin on the line. For the downstream direction, if there is excess margin, then IOS displays a reduction in margin for the modes listed above, and a reduction in transmit power for T1.413 mode. For the upstream direction, if there is excess margin, then IOS displays a reduction in the margin for g-992-1 mode only. IOS will not display a reduction in transmit power for the upstream direction.
ATM OAM Cells Supported in Fast Path Mode
The NI-2 now supports atm oam cells through fast path mode. Also, you can now use the ping atm utility command in fast path mode.
Enhanced ATM OAM Segment Cells Support
A new command, atm oam intercept segment, allows you to enable or disable receiving atm oam segment cells on valid connections. By default, the atm oam cells received on unconfigured or down connections are dropped. For more information, see the Command Reference for Cisco DSLAMs with NI-2.
MIB Object Changes
This release contains changes to the following Management Information Base (MIB) objects:
The power management feature is configurable via the CISCO-ADSL-DMT-LINE-MIB. The mib object cAdslAtucDmtConfPMAddSnrMgn configures the downstream component and the mib object cAdslAturDmtConfPMAddSnrMgn configures the upstream component on that particular dsl profile. Both objects default to 0 and can be configured from 0 to 150 tenths of dBs in increments of 10. Setting the objects to 0 explicitly via SNMP will disable the power management feature on the ports.
Update the Image in Bootflash to the 12.2(10)DA4 dboot Image
When you upgrade from Cisco IOS Release 12.1(5)DA2 or earlier images on the NI-2 card to Release 12.2(10)DA4, you must reformat the bootflash on the NI-2 card.
Note If you are upgrading from Cisco IOS Release 12.1(6)DA, 12.1(6)DA2, 12.1(7)DA, 12.1(7)DA2, 12.1(7)DA3, 12.2(1b)DA, 12.2(1b)DA1, 12.2(5)DA, 12.2(5)DA1, 12.2(7)DA, 12.2(10)DA, 12.2(10)DA1, 12.2(10)DA2, or 12.2(10)DA3 you do not need to reformat the bootflash. You can skip this section and follow the DSLAM upgrade procedure at the following URL:
Note We highly recommend that you have console access to the NI-2 card during the upgrade procedure. You can use the console connection to troubleshoot any unexpected events that occur during the upgrade.
To update the boot image, perform the following steps in privileged EXEC mode:
DSLAM# dir bootflash:
Verify that the bootflash image is ni2-dboot-mz.121-5.da4 or ni2-dboot-mz.121-4.da. If it is neither, go to the "Upgrade the Bootflash Image on the NI-2 Card to the 12.1(5)DA2 dboot Image" section and perform the instructions there, and then return to this step. This is required because of a problem (CSCdr89374) in old bootflash images.
DSLAM# dir flash:
Display the name of the Flash file that begins ni2- and use it as filename in Step 3.
DSLAM# delete flash:filename
DSLAM# squeeze flash:
Recover available space in Flash memory.
DSLAM# copy tftp://tftpserver:TFTPBOOT/ni2 -dsl-mz.122-10.da4 flash:
Copy the Cisco IOS image from a TFTP server to Flash.
DSLAM# configure terminal
DSLAM (config)# no boot system
DSLAM (config)# boot system flash:ni2-dsl-mz.122-10.da4
Enter global configuration mode.
Disable the boot from system.
Specify the name of the system image to load at startup.
End global configuration mode.
DSLAM# copy running-config startup-config
Save your changes to the startup configuration.
Reload the system to upgrade the image.
DSLAM# show version
Confirm that the running image is ni2-dsl-mz.122-10.da4. If it is not, go to Step 5.
DSLAM# format bootflash:
Erase all information in bootflash memory. Answer y to all confirm questions. When the DSLAM returns you to the EXEC prompt, bootflash memory is successfully formatted and ready for use.
Ensure that the bootflash is 3.8 MB total. If it is not, go to Step 5.
DSLAM# copy tftp://tftpserver:TFTPBOOT/ni2 -dboot-mz.122-10.da4 bootflash:
Copy the boot image from a TFTP server to the bootflash.
Reload the system to upgrade the image.
Upgrade the Bootflash Image on the NI-2 Card to the 12.1(5)DA2 dboot Image
When you upgrade from Release 12.1(3)DA or earlier images on the NI-2 card to Release 12.1(5)DA2, we recommend that you upgrade the bootflash image on the NI-2 card to the 12.1(5)DA1 dboot image.
To upgrade the dboot image in bootflash, perform the following steps:
Limitations and Restrictions
This section describes the limitations and restrictions for Cisco IOS DSLAM releases.
Attainable Bit Rate Is Conservative on 4xflexi-DMT and 8xDMT
The reported DMT aggregate bit rate is less than the true attainable bit rate.
Due to line condition variations between trains, the effect of trellis coding, interleave delay, FEC check bytes, and so forth, the attainable bit rate estimate is not always 100 percent accurate. A conservative approach was taken in making the estimate; therefore, in general, you can get a higher rate than what the estimate suggests. For a fast-path scenario, the results should track fairly closely for the downstream rate and err on the conservative side for the upstream rate. For an interleave path scenario, the results are highly dependent on configurations.
At a higher reach or where line conditions are not optimal, the effect of having trellis coding, interleave delay, and FEC check bytes can provide a much higher rate than was estimated (greater than 128 kbps).
There is no workaround. The aggregate bit rate calculation is an estimate, which does not accurately model all of the line conditions that affect the true attainable bit rate for a given profile. The calculations for aggregate bit rate are performed as follows:
•The downstream capacity is obtained from the number of Reed-Solomon payload bytes per frame exchanged during line training, that is, the K value. The per-second estimate is then calculated from this K value. An extrapolated margin value is derived from the per-second estimate to make sure that if the line is trained at the estimated rate, it will still have an adequate margin.
•For upstream, unlike downstream, the Reed-Solomon payload bytes per frame is not readily available. Furthermore, unlike downstream, which requires a CPE EOC response to know the downstream margin, the upstream margin is readily available at the CO (upstream margin is measured at the CO end). Using this upstream margin and the number of bins utilized for upstream, an estimate of upstream attainable bit rate is made. (The associated DDTS numbers are CSCdv05351 and CSCdv05322.)
CPE Performance Issues with Overhead Framing Modes 0, 1 and 2
The customer premises equipment (CPE) does not train or perform reliably when the Discrete Multitone (DMT) profile is set to use overhead framing mode 0, 1, or 2.
Overhead framing modes 0, 1, and 2 are not supported at this time.
Overhead framing mode 3 is designed for use in Asynchronous Transfer Mode (ATM). While overhead framing mode 1, which is not currently supported, is designed for Synchronous Transport Module (STM) mode. Configure your profiles to use overhead framing mode 3. Overhead framing mode 3 uses only 32 bytes of administrative overhead. Compared with overhead framing mode 1, it allows more bandwidth to be allocated to user data.
Trellis Coding Enable Default Recommendations
Trellis coding is disabled by default on the NI-2 because it is not supported on the 4xDMT (ATUC-1-4DM) card. However, trellis coding is supported on the 4xFlexiDMT (ATUC-4FLEXIDMT) and 8xDMT (ATUC-1-DMT8) line cards. Additionally, trellis coding should be enabled for the 4xFlexiDMT and 8xDMT line cards.
For all 4xDMT (ATUC-1-4DMT) ports in the DSLAM, make sure that trellis coding is disabled in the dsl-profile for those ports. For all 4xFlexiDMT and 8xDMT ports in the DSLAM, make sure that trellis coding is enabled except with ADI chipset based CPE using ADI F/W prior to ADI 3.1. This includes all Cisco 677 and Cisco 627 CPEs.
See the documentation at the following location for details on the commands used to change trellis coding settings on the NI-2:
Restrictions on NI-2 IP Services
This section describes restrictions on Cisco NI-2 IP services.
Restricted Layer 3 Services
Cisco IOS Release 12.2(10)DA does not support the following Layer 3 services (or else these services are limited, as noted):
•IP Quality of Service.
•L2TP Tunnel Priority and Limit sessions.
•L2TP Network Server (LNS).
•The maximum number of MPLS/VPN for PPPoA terminations is 25 VPNs for PPPoA and 1 VPN for PPPoE.
•We recommend use of a virtual template for PPPoX termination rather than a dialer interface.
•MPLS LDP protocol is not supported in this release. Use TDP protocol.
•Up to 32 subinterfaces can be used for IP termination under the trunk or subtend ports.
•Each DSLAM can support up to 50 MPLS VPNs.
Integrated Routing and Bridging Not Supported
MPLS VPN mapping of RFC 1483 routed sessions must not be confused with Integrated Routing and Bridging (IRB). IRB is not supported by MPLS VPN mapping of RFC 1483 routed sessions.
VPN Interfaces Restricted to Trunk Interfaces
Do not configure subtended interfaces for MPLS VPN services. Only trunk interfaces support MPLS VPN mapping of RFC 1483 routed sessions.
MPLS ATM-Label Switch Router Functionality Not Supported
DSLAMs are not meant for use as MPLS ATM-Label Switch Routers (ATM-LSRs). When designing your network, keep in mind that DSLAMs act only as Label Edge Routers (LERs).
Performance Restrictions for MPLS VPN Traffic
MPLS VPN-enabled interfaces do not perform as well as switched VCs. Please take this into consideration when deploying MPLS VPNs in your networks.
Restricted MPLS Features
The following MPLS-related features are not part of MPLS VPN mapping of RFC 1483 routed sessions:
•MPLS traffic engineering
DSL Interface Limitations
In DSLAMs, each DSL interface can support multiple permanent virtual circuits (PVCs), but we recommend that you use one routed MPLS VC if a dynamic routing protocol, such as RIP, is used between the CE and the PE.
MPLS VPN Mapping Not Supported on the Eight-Port IDSL ITU-C Line Card
Routed termination of IDSL connections is not supported since Cisco IOS Release 12.2(1b)DA.
Frame Relay PVCs/Soft PVCs on an IDSL Interface
The number of Frame Relay PVCs/Soft PVCs on an IDSL interface is restricted to 1 if you use the default row in a frame-relay connection traffic table (FR-CTT).
When upgrading to Release 12.2(10)DA4 from previous releases, you must first create a new row in the FR-CTT with the desired CIR value and use the resultant row number during PVC/Soft PVC creation. If you do not create a new row, the second FR PVC/Soft PVC command is not parsed and installed on the IDSL interface.
Use of a Ring Topology in a DSLAM Subtend Environment to Achieve ATM Trunk Redundancy
Ring topology is achieved when a node in the subtend tree is attached to the ATM access to provide a physically redundant loop. Thus, when the primary ATM access or one of the ATM trunks in the subtend tree fails, the soft permanent virtual circuits (SPVCs) can be dynamically rerouted through the use of Private Network-Network Interface (PNNI). See Figure 1.
Figure 1 SPVCs Prior to Failure
This redundancy requires the use of SPVCs. If you use permanent virtual circuits (PVCs) or permanent virtual paths (PVPs), redundancy cannot be provided. The use of the SPVCs allows traffic to be rerouted around the failed access point, because SPVCs leverage this feature of PNNI. When the failure occurs, the SPVCs are disconnected and dynamically reconnected across the new path. See Figure 2.
Figure 2 SPVCs Dynamically Rerouted
If you implement ring topology in a DSLAM subtend to achieve ATM trunk redundancy, the following requirements apply:
•You must use SPVCs, PNNI, ATM signaling, and Interim Local Management Interface (ILMI) to enable rerouting. PNNI, ATM signaling, and ILMI are enabled by default. Permanent connections such as PVCs and shaped virtual paths (VPs) do not benefit from the redundant link.
•You must make the redundant link's PNNI administrative weight higher than the PNNI weight of the primary trunk. Once you change the weight of the redundant link, the subtend tree uses this link only if a failure occurs.
When the redundant link is active, the following occurrences are problems:
•Loss of subtending fairness.
•Increase in latency as well as an increase in cell delay variation (CDV) between the cells. Delay-sensitive traffic, such as voice and video, or traffic that is susceptible to jitter, such as constant bit rate (CBR) voice, might be compromised. This technique is best realized for unspecified bit rate (UBR) traffic, such as consumer internet access, where no strict quality of service (QoS) objectives are required.
Once the redundant link is active, the following occurrences are potential problems:
•Greater possibility of increased congestion in the DSLAM ATM switch fabric, which might cause loss of data.
•When the main link is restored, there is downtime while the path is being rerouted. After the SPVCs are rerouted to the redundant ATM trunk and the original trunk is repaired or brought back into service, you must manually intervene. You must flap (shut/noshut) the subtend port. Because of retries on the current path, you must keep the trunk down until the maximum retry interval expires.
Cisco DSL Manager
If you are using versions of Cisco DSL Manager (CDM) before CDM Release 3.4—from CDM Release 1.0 to CDM Release 3.3(3)—do not upgrade the DSLAMs to this new Cisco IOS release.
If you use both the CDM network management application and the Cisco IOS command line interface to manage your Cisco DSLAMs, you should be aware of certain configuration and procedural implications. Please refer to the Release Notes for the Cisco DSL Manager, Release 3.4 for this information.
This section provides important information about Cisco IOS DSLAM releases.
Line Card Features
Table 2 shows which line card features are available on the 4xDMT, 4xFlexi, and 8xDMT line cards.
Table 2 Line Card Features
NI-2 IP Services
During system startup, the following protocol warning messages display. You can ignore these messages.
•If RADIUS is configured:%AAAA-4-SERVUNDEF: The server-group "radius" is not defined. Please define it.
•If VPN is configured:% Can't create VRF
Soft PVC Address Changes upon Upgrade from Release 12.1(4)DA or Earlier
When you upgrade from Cisco IOS Release 12.1(4)DA or earlier to Release 12.2(10)DA4, the default soft PVC addresses on all interfaces change. This occurs only when you upgrade to Release 12.2(10)DA4 from Release 12.1(4)DA or earlier.
Reconfigure the soft PVCs associated with all interfaces.
Assign a (nondefault) address to the interfaces.
Configuring Cisco Routers for Use with IDSL
If you wish to use a Cisco router for an IDSL application and the router is running a Cisco IOS release prior to Release 12.1, you must configure the ISDN switch type. If you do not configure the ISDN switch type on the Cisco router, the router's BRI interface might not come back up after the IDSL line goes down and comes back up.
To prevent this problem from occurring, execute the isdn switch-type basic-ni command in global configuration mode on the router.
This problem does not occur if the Cisco router is running Cisco IOS Release 12.1 or later.
Assigning VPI Values to Shaped VP Tunnels
This release supports the full range of VPI values: 0 to 255. However, if you configure VP tunnels with traffic shaping, you can use only 32 VPIs out of that range. If you have not yet assigned any VPIs, all values from 0 to 255 are available. Once you start assigning VPIs, however, the assigned VPIs limit the VPIs that remain. (You assign VPIs using the atm pvp or atm pvc command.)
After a particular VPI value is assigned to a shaped VP tunnel, every 32nd VPI value above and below the first one is eliminated—that is, the original value modulo 32. For example, if you assign VPI 94 to a shaped VP tunnel, the following VPI values become unavailable for any purpose: 30, 62, 126, 158, 190, and 222.
To avoid problems, choose a block of 32 consecutive VPI values (for example, 0 to 31 or 101 to 132). The software rejects invalid VPI values.
Installing Multiple Cisco 6160 Chassis in an Equipment Rack
You can install multiple Cisco 6160 chassis in a telco equipment rack. A standard 7-foot equipment rack can house four Cisco 6160 chassis, stacked one on top of another. This configuration maximizes the DSL density within a 7-foot rack. However, if space is available or if you are interested in using multiservice capabilities that the chassis will support in the future, we recommend that you install no more than three Cisco 6160 chassis within a 7-foot rack. Leave a space of at least 2.5 rack units (4.375 inches, or 11.1 cm) beneath each chassis for future cable management use.
Turn console logging off if you plan to reboot the DSLAM. Turn console logging back on after the system comes up. (Console logging is turned on by default.) Use the global configuration commands no logging console (to turn the feature off) and logging console (to turn it on).
If console logging is on when the system reboots, the large volume of console messages consumes CPU time. As a result, the system comes back up more slowly and line cards might reload repeatedly, causing further delays.
Caveats describe unexpected behavior in Cisco IOS software releases. Severity 1 caveats are the most serious caveats; severity 2 caveats are less serious. Severity 3 caveats are moderate caveats, and only select severity 3 caveats are included here.
This section contains only open, closed, and resolved caveats for the current Cisco IOS release.
Caveat numbers and brief descriptions are listed inTable 4, Table 5, Table 6, Table 7, and Table 8. For details about a particular caveat and for information on caveats in previous Cisco IOS releases that also apply to this release, go to Bug Toolkit at:
To access this location, you must have an account on Cisco.com. If you have forgotten or lost your account information, e-mail the Contact Database Administration group at email@example.com. If you do not have an account on Cisco.com, go to http://www.cisco.com/register and follow the directions to set up an account.
Note If you have an account with Cisco.com, you can use Bug Navigator II to find caveats of any severity for any release. To reach Bug Navigator II, go to Cisco.com and click Login. Then go to Software Center > Cisco IOS Software > Cisco Bugtool Navigator II. Alternatively, you can go to
This software release is based on Cisco IOS Release 12.2. For information on caveats in Cisco IOS Release 12.2, see Caveats for Cisco IOS Release 12.2, which lists severity 1 and 2 caveats and select severity 3 caveats for Cisco IOS Release 12.2. It is located on Cisco.com and the Documentation CD-ROM.
Resolved Caveats—Release 12.2(10)DA4
Table 3 lists the caveats that have been resolved in Cisco IOS Release 12.2(10)DA4.
Table 3 Resolved Caveats in Cisco IOS Release 12.2(10)DA4
Caveat Number Description
Unable to telnet
Not able to telnet to card (No Free TTYs error)
BGP: insufficient chunk messages with many VPN routes
BGP shouldn't propagate an update with excessive AS Path >255
Cisco IOS may permit arbitrary code execution after exploitation of a heap-based buffer overflow vulnerability. Cisco has included additional integrity checks in its software, as further described below, that are intended to reduce the likelihood of arbitrary code execution.
Cisco has made free software available that includes the additional integrity checks for affected customers.
This advisory is posted at http://www.cisco.com/warp/public/707/cisco-sa-20051102-timers.shtml.
Resolved Caveats—Release 12.2(10)DA3
Table 4 lists the caveats that have been resolved in Cisco IOS Release 12.2(12)DA3.
Resolved Caveats—Release 12.2(10)DA2
Table 5 lists the caveats that have been resolved in Cisco IOS Release 12.2(12)DA2.
Open Caveats—Release 12.2(10)DA1
All the caveats listed in Table 6 are open in Cisco IOS Release 12.2(10)DA1. This table lists only severity 1 and 2 caveats and select severity 3 caveats.
Resolved Caveats—Release 12.2(10)DA1
Table 7 lists the caveats that have been resolved in Cisco IOS Release 12.2(12)DA1.
Resolved Caveats—Release 12.2(10)DA
The problems listed in Table 8 are fixed in Cisco IOS Release 12.2(10)DA.
The software described in these release notes runs on several Cisco NI-2 DSLAM platforms, including the Cisco 6015 DSLAM, Cisco 6160 DSLAM, and Cisco 6260 DSLAM. The sections below list related documentation.
A complete list of all DSL hardware product related documentation is available on the World Wide Web at
A complete list of all DSL Cisco IOS product related documentation is available on the World Wide Web at
In the Cisco ATM software manuals, look for information pertaining to the LightStream 1010, which uses the same software base as the NI-2 DSLAMs. ATM manuals are on the World Wide Web at
The following sections provide sources for obtaining documentation from Cisco Systems.
World Wide Web
You can access the most current Cisco documentation on the World Wide Web at the following sites:
Cisco documentation and additional literature are available in a CD-ROM package that ships with your product. The Documentation CD-ROM is updated monthly and is available as a single unit or through an annual subscription.
•Registered Cisco.com users can order the Documentation CD-ROM through the online Subscription Store:
•Nonregistered Cisco.com users can order the Documentation CD-ROM through a local account representative by calling Cisco corporate headquarters (California, USA) at 408 526-7208 or, in North America, by calling 800 553-NETS(6387).
•For assistance with ordering, contact your distributor or see the Cisco Technical Assistance Center website at:
If you are a registered Cisco.com user, you can submit technical comments electronically.
•To report problems, click Feedback in the toolbar at the top of any document web page and select Report a Problem. Under Problem Type, select CD/Online Documentation. After you complete the form, click Submit to send it to Cisco.
You can also e-mail your comments to firstname.lastname@example.org.
•To send your opinion of the DSL documentation, go to the following URL:
and click here at the top of the page in the sentence "Is this Cisco documentation helpful? Click here to give us your feedback." This produces a Documentation Survey that you can complete and send to Cisco electronically.
To submit your comments by mail, write to the following address:
Attn: Document Resource Connection
170 West Tasman Drive
San Jose, CA 95134-9883
We appreciate your comments.
Obtaining Technical Assistance
Cisco provides Cisco.com as a starting point for all technical assistance. Customers and partners can obtain documentation, troubleshooting tips, and sample configurations from online tools. For Cisco.com registered users, additional troubleshooting tools are available from the TAC website.
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Cisco.com provides a broad range of features and services to help customers and partners streamline business processes and improve productivity. Through Cisco.com, you can find information about Cisco and our networking solutions, services, and programs. In addition, you can resolve technical issues with online technical support, download and test software packages, and order Cisco learning materials and merchandise. Valuable online skill assessment, training, and certification programs are also available.
Customers and partners can self-register on Cisco.com to obtain additional personalized information and services. Registered users can order products, check on the status of an order, access technical support, and view benefits specific to their relationships with Cisco.
To access Cisco.com, go to the following website:
Technical Assistance Center
The Cisco TAC website is available to all customers who need technical assistance with a Cisco product or technology that is under warranty or covered by a maintenance contract.
Contacting TAC by Using the Cisco TAC Website
If you have a priority level 3 (P3) or priority level 4 (P4) problem, contact TAC by going to the TAC website:
P3 and P4 level problems are defined as follows:
•P3—Your network performance is degraded. Network functionality is noticeably impaired, but most business operations continue.
•P4—You need information or assistance on Cisco product capabilities, product installation, or basic product configuration.
In each of the above cases, use the Cisco TAC website to quickly find answers to your questions.
To register for Cisco.com, go to the following website:
If you cannot resolve your technical issue by using the TAC online resources, Cisco.com registered users can open a case online by using the TAC Case Open tool at the following website:
Contacting TAC by Telephone
If you have a priority level 1(P1) or priority level 2 (P2) problem, contact TAC by telephone and immediately open a case. To obtain a directory of toll-free numbers for your country, go to the following website:
P1 and P2 level problems are defined as follows:
•P1—Your production network is down, causing a critical impact to business operations if service is not restored quickly. No workaround is available.
•P2—Your production network is severely degraded, affecting significant aspects of your business operations. No workaround is available.