Introduction to Software Maintenance Upgrade
The Software Maintenance Upgrade (SMU) is a package that can be installed on a system to provide a patch fix or a security resolution to a released image. A SMU package is provided for each release and is specific to the corresponding platform.
A SMU provides a significant benefit over classic Cisco IOS software because it allows you to address the network issue quickly while reducing the time and scope of the testing required. The Cisco IOS XE platform internally validates the SMU compatibility and does not allow you to install noncompatible SMUs.
All the SMUs are integrated into the subsequent Cisco IOS XE software maintenance releases. A SMU is an independent and self-sufficient package and does not have any 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 for the full lifecycle of the underlying software release. |
Note |
You can activate the file used in the install add file command only from the filesystems of the active device. You cannot use the file from the standby or member filesystems; the install add file command will fail in such instances. |
Note |
When the SMU file is deleted and a reboot is performed, the device may display the following error message:
This error occurs because the previous SMU file was not properly removed from the controller. It may lead to functional errors, such as the inability to install new SMU or APSP files. We recommend that you use the install remove file command to remove previous instances of APSP or SMU files from the bootflash. |
SMU infrastructure can be used to meet the following requirements in the wireless context:
-
Controller SMU: Embedded Wireless Controller bug fixes or Cisco Product Security Incident Response information (PSIRT).
-
AP bug fixes, PSIRTs, or minor features which do not require any embedded wireless controller changes.
-
APDP: Support for new AP models without introduction of new hardware or software capabilities.
Note |
The show ap image command displays cumulative statistics regarding the AP images in the controller. We recommend that you clear the statistics using the clear ap predownload statistics command, before using the show ap image command, to ensure that correct data is displayed. |
SMU Workflow
The SMU process should be initiated with a request to the SMU committee. Contact your customer support to raise an SMU request. During the release, the SMU package is posted on the Cisco Software Download page and can be downloaded and installed.
SMU Package
An SMU package contains the metadata and fix for the reported issue the SMU is requested for.
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 flow for the duration of the reload (~5 min currently). 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. |
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
--------------------------------------------------------------------------------
Auto abort timer: inactive
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