CIMC configuration and access on standby WLC 5520

[c-davies]

Hello, 

I have configured two 5520 WLC one as primary and one has SSO HA which is working fine.

However I want to configure the CIMC on both units but the controller command line doesnt let me define the standby CIMC IP Address, infact the single command is syned to the standby WLC.

I applied the  imm address ip-addr net-mask gateway-ip-addr. 

commands this works I can web to that IP address but how do I get to the standby WLC's CIMC??

I am remote to the units so right now my only option is controller commandline. 

I have been using these resources

http://www.cisco.com/c/en/us/td/docs/wireless/controller/5500/5520/installation/guide/wlc-ig-5520/overview.html#pgfId-1281012

http://www.cisco.com/c/en/us/td/docs/wireless/controller/technotes/8-1/5520-WLC-DG/b_Cisco-5520-WLC-deployment-guide.html

Thanks for your help.

[Rasika Nayanajith]

I would simply leave CIMC to be DHCP and reserve IP address in DHCP server for that MAC address.

HTH

Rasika

*** Pls rate all useful responses ***

[c-davies]

Thanks, its an option but my customer would prefer statically fixing the IP Address, they don't want to have to create a DHCP pool for just 2 devices. Mind you if that's how everyone else does it... I guess a dhcp server could be configured on the switch..

[Rasika Nayanajith]

Otherwise you can do this when these devices initially configured (CIMC setup menu). Since now this is in production with HA, not sure whether you can do it without breaking HA.

DHCP option should be the simple fix.

HTH

Rasika

*** Pls rate all useful responses ***

[pieterh]

you can try adding a static ARP entry on the gateway tot this CIMC subnet, to attach an ip-address to the MAC address of the CIMC.
Maybe this allows you to access the CIMC for configuration, then remove the static arp.

[Johannes Luther]

I don't know if this is supported, but you can always boot the WLC with an attached serial console. During boot - before the WLC booting process, a prompt will come up to press F8 in order to configure the CIMC (as for all UCS based servers).

In the following text based UI, you can edit the IP address parameters.

CAUTION:

• Do not change the NIC mode to shared. It should be in dedicated mode
• Do not change the FlexFlash Mode
• Do not change the SSD/Virtual disk settings
• BIOS parameters should not be changed

Expectations when logged in via CIMC

• FlexFlash is configured for RAID but only one flash is populated this causes CIMC to show the FlexFlash as degraded.We can safely dis-regard the FlexFlash degradation warning in our case.
• Expect to see only one CPU populated
• Do not configure Software Raid on SSD

Just a side note - I would like to configure just SNMP (poll and trap) to the CIMC.

I think/hope/guess this is a more reliable way to monitor the health status of the secondary WLC as with WLC integrated traps (like HDD failure, memory failure etc.). Hopefully, there will be a statement of Cisco at some time, that this is "officially" supported, without breaking the WLC.

[KAF]

Hi,

i just had exactly the same issue. Two WLC 5520 in HA at a remote site. And i'm off the opinion that this behavior of syncing the CIMC ip address to both machines when HA is enabled is some kind of design flaw. The command should not sync to both machines and there should be some kind of "imm peer address" command to be able to set the IP address of the secondary machine as well.

But still I was able to solve this issue without any interruption:

1. Login to WLC CLI using SSH to Management IP Address.
2. Issue "show inventory" and take a note of the serial number.
3. Issue "show redundancy summary" and make sure the state is "STANBY HOT" and BulkSync Status is "Complete" and your connected to Primary Unit.
4. Issue "imm address <ipaddr1> <netmask> <gateway>" and "imm dhcp disable" as advised. IP Address will be synced to both WLC-CIMC, as far as i experienced (duplicate IP address...).
5. Issue "redundancy force-switchover". The primary unit will reboot and secondary unit will take its place immediately.
6. You will probably lose SSH connection. If so, reconnect to WLC CLI using SSH to Management IP Address.
7. Issue "show inventory" and take a note of the serial number.
8. Issue "show redundancy summary" and you will notice, that the state is unknown and you are connected to the secondary unit, which is currently active.
9. Issue "imm address <ipaddr2> <netmask> <gateway>" and "imm dhcp disable" as advised. This time the IP address will only be synced to the secondary unit, since the primary unit is still rebooting.
10. Now connect to both CIMC IP addresses using HTTPS in a browser and compare before noted serial numbers as verification. You now should have both CIMC interfaces configured correctly. Yay! :)
11. Back to WLC CLI. We have to cleanup now: Issue "show redundancy summary" and make sure the primary unit is back up and state is "STANDBY HOT" again and BulkSync Status is "Complete". Notice the current active uni is still the secondary unit.
12. Issue "redundancy force-switchover" again for the primary unit to become the active unit again.
13. After a couple of minutes issue "show redundancy summary"to make sure the secondary unit is back up again (State is "STANBY HOT" and BulkSync Status is "Complete").

I hope this will work for you. I had no problems and experienced no outtages or any disruptive behaviors at all.

Disclaimer: I still don't take any responsibilities in case anything goes wrong and i don't guarantee the 100% correctness of this guide. When in productive environment, always do this kind of work in maintenance windows.

Best Regards!

[kumarpadala]

This method isn't working on my current setup. I have two 5520 wlc with HA, and I have configured static IP on Primary CIMC port, and I reloaded the primary wlc, then I logged into secondary wlc (running as primary), surprisedly IMM also replicated to secondary wlc (which means I saw static IP on current wlc, which I configured on primary wlc).

is there any other process available except shutting down one wlc and configure the second wlc CIMC port ?

[Joel Frye]

I recently encountered this issue and this is the process TAC suggested on my 8540 HA pair:

So to proceed with CIMC configuration on the standby you need to break HA first.

When the Controller is in HA pair, you can try to go for CIMC configuration by doing failovers but that does not guarantee that disruption won’t be caused.

I prefer to disable HA on secondary so that your primary is up and running and once CIMC configuration is done, you can enable HA again on standby so that means you will only end up rebooting secondary controller.

[tadnan001]

It is a known bug CSCvf57867:

https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvf57867

Symptom:
have two controllers in HA (AP-SSO) try to configure IMM for active and standby. However, only a single IP gets synced to both active and standby.

[CfYz]

It's very easy to do so! I've got 5520 8.2 HA pair and configuration of CIMC by default (DHCP+0.0.0.0+default login/password) and have the same problem.

So before - you need access to router when the IP interface to CIMC will be used, and a switch where physically connected M ports to network or you can ask person responsible for this devices to help you.

1. Shutdown port on switch to standby WLC CIMC M port;

2. Configure CIMC by imm commands (https://www.cisco.com/c/en/us/support/docs/wireless/5520-wireless-controller/212170-Console-access-to-5520-8540-WLC-via-CIMC.html);

3. Access CIMC from HTTP, note serial or simple write the server Description;

4. Shutdown port on switch to active WLC CIMC M port, clear arp to configured IP on router and up the standby CIMC M port back;

5. Access standby CIMC from HTTP from same IP address and change it to whatever you want.

So this method is better because you don't need to force-switchover anything and no risk at all on interruption to production traffic.