Upgrading ACE , redundant active-active context

[filterfilter]

Hi,

We have 2 ACE's running in our network, and we would like to upgrade the ACE software.

To minimize any disruption to existing network traffic during a software upgrade or downgrade, deploy your ACE modules in a redundant configuration. For details about redundancy, see Chapter 7, Configuring Redundant ACE Modules. The following steps provide an overview on upgrading a redundant configuration used in conjunction with the procedures in this appendix:

1. Upgrade the active module first.

2. Reboot the active ACE after the software installation. When you reboot the active ACE, it fails over to the standby module and existing traffic continues without interruption.

3. Upgrade the new active module.

4. Reload the active ACE after the redundant module is up and the high availability (HA) state is hot. A similar failover occurs when you reboot this ACE and once again the existing traffic continues. The original active ACE is active once again.

http://www.cisco.com/en/US/docs/interfaces_modules/services_modules/ace/v3.00_A1/configuration/administration/guide/upgrade.html

This section describes the methods and CLI commands that you can use to troubleshoot redundancy issues in your ACE.

1. Ensure that the software versions and licenses installed in the two ACEs are identical. A software or license mismatch may generate the following syslog message:

                              %ACE-1-727006:       HA: Peer is incompatible due to error str. Cannot be Redundant.

http://docwiki.cisco.com/wiki/Cisco_Application_Control_Engine_(ACE)_Module_Troubleshooting_Guide,_Release_A2(x)_--_Troubleshooting_Redundancy

Following those step, is there any problem would happen after step 2 , having a different software version on the first and second module?

also on step 4 ' Reload the active ACE after the redundant module is up and the high availability (HA) state is hot. ' , is that possible with both module use a different software version ?

[sivaksiv · Accepted solution]

Hi,

When you upgrade or downgrade the ACE software in a redundant  configuration with different software versions, the STANDBY_WARM and  WARM_COMPATIBLE states allow the configuration and state synchronization  process between the peers to continue on a best-effort basis. This  basis allows the active ACE to synchronize configuration and state  information with the standby even though the standby may not recognize  or understand the CLI commands or state information.

In the STANDBY_WARM state, as with the STANDBY_HOT state,  configuration mode is disabled on the standby ACE and configuration and  state synchronization continues. A failover from the active to the  standby based on priorities and preempt can still occur while the  standby is in the STANDBY_WARM state. However, while stateful failover  is possible for a WARM standby, it is not guaranteed. In general,  modules should be allowed to remain in this state only for a short  period of time.

http://docwiki.cisco.com/wiki/Cisco_Application_Control_Engine_%28ACE%29_Module_Troubleshooting_Guide,_Release_A2%28x%29_--_Troubleshooting_Redundancy#About_WARM_COMPATIBLE_and_STANDBY_WARM

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Siva

[filterfilter]

thx siva..

i should really read the whole document tho,