Swapping two WLCs

[Giuliano Gerardi]

Let's say:

we have 4 wlc 5508 (not HA)

1-2 have 112 ap hard-licences and servicing site1

3-4 have 50 ap hard-licences and servicing site2

now I need to swap wlc2 with wlc3 to prepare for HA migration (On Sunday)

the wlc3 will be backupped and disconnected from the network

the wlc2 will be backupped restored with wlc3 backup and moved to wlc3 position

on wlc3 will be restored wlc2 backup and moved to wlc2 position

Will this work?

I cannot find any cisco doc where it is specified this kind of procedure (even in case of disaster recovery and wlc failure/rma)

I'm a little bit concerned about passwords/hashes and everything to go right way

If you can think about any warning doing this please let me know

[Scott Fella]

If you are going to swap WLC's, then you just need to move the AP's to WLC1 and WLC4.  Do this by changing the high availability on the access point.  When the ap's move, then you can do what you have to do, but you will have downtime as you have to possibly upgrade to v7.4.100.60 for HA, and enable AP SSO.  HA on this code is more stable than any other code, but not 100% perfect.  Just make sure you have smartnet before doing this in case you need to call TAC.  The reason I say this, is because it can be very simple to a pain in the BUTT:)

Good luck and follow up with any issue that might come up.

Thanks,

Scott

Help out other by using the rating system and marking answered questions as "Answered"

[Giuliano Gerardi]

Thank you Scott

no problem for downtime as it will be done on sunday and the AP are configured with primary and secondary respective site wlcs

I've read 7.4.100.60 is a beta ...  so we were preferring 7.4.100.0...

however my question was a little bit different...

do you think this backup cross-restoring is likely to be successful or there can be issues when trying to restore a bakup taken from wlc3 to wlc2?

[Scott Fella]

okay... v7.4.100.60 is recommended if going with HA.... this is important!!!!!

When you are removing the WLC2 & WLC3, I would factory reset them and make sure that any code version upgrade, certificate and webauth bundles get uploaded before you enable AP SSO.  No restore should be done!!!! Make sure that the WLC1 & WLC4 is configured properly before enabling AP SSO.

Thanks,

Scott

Help out other by using the rating system and marking answered questions as "Answered"

[Giuliano Gerardi]

maybe I was misleading

let's try to make clearer:

wlc2 will be primary for site2 HA (this is important as it has 112 licences but I need it to have site2 configuration on it)

wlc3 will be secondary for site1 HA

as the wlc 2 has site1 configuration I need to load onto ite the backup of wlc3 with site 2 config (still guessing if it will work)

then I will erase wlc3 before enabling SSO as it will be secondary for site1 HA and controlled by wlc1 which is ok

wlc4  will be factory resetted too right before enabling SSO

TY again

[Scott Fella]

Yeah thats a bit confusing as you would want the AP's to be on the primary WLC before you enable AP SSO.  Anyways, since you have downtime, it doesn't matter if the wireless is up or not.  You might be better off removing the WLC's from the network since you are swapping primary's.  This way you can backup, factory default and restore the config to WLCx.

Thanks,

Scott

Help out other by using the rating system and marking answered questions as "Answered"

[Giuliano Gerardi]

Yep

we don't care about downtimes

removing wlc3 (primary for site 2) will lead to ap migration to wlc4 (secondary for site2)

removing wlc2 (secondary for site1) will not change anything as all site1  APs will be on Wlc1 (primary for site1)

so you are suggesting to factory reset wlc2 before pushing onto it wlc3 config

(still guessing if this restoration of wlc3 will be successful on wlc2...)

then I will wait for the AP to correcly associate to the new site2 primary

reset the secondary for both sites and only then enable SSO

TY

[Scott Fella · Accepted solution]

You can always restore, but to be safe, factory default the WLC before you upload a backup config from another WLC.  The reason you would disconnect the WLC's from the network is in case you end up with duplicate ip address from the WLC's.  Restore the config doesn't fix everything as you still need to look at you mobility group settings.

Thanks,

Scott

Help out other by using the rating system and marking answered questions as "Answered"

[Giuliano Gerardi]

thank you very much Scott

your help is really appreciated!