Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
New Member

WLC 5508 7.4.X - N+1

Hi,

I don't undestand this document

http://www.cisco.com/c/en/us/td/docs/wireless/technology/hi_avail/N1_High_Availability_Deployment_Guide/N1_HA_Overview.html

How can the third 5508 (suport max 500 AP) backup all other WLC ? n+1 how ?

With secondary wlc configured in HA-SKU (without AP SSO) the 500 licenze are permanent ?

who can explain me.. this is a document bug ??

8 REPLIES

WLC 5508 7.4.X - N+1

What they're describing is HA N+1, not HA 1:1 AP SSO.  This option, which is "NON-AP-SSO", allows you to use an HA-SKU or > -50-k9 SKU coverted, to operate as a dedicated +1 WLC in HA.  When using this configuration, this WLC allows the use of the "hardware maximum" of the device: Thus 500 APs for WLC 5508, or 1000APs for a WISM2 (as an example).  Since this WLC can wait as a backup to multiple WLCs, that's why it's not capable of the AP SSO, which requires a 1:1 pairing of the HA WLC with an Active HA WLC.

When using the HA N+1 the WLC acts the same as the pre AP-SSO "HA" concept; where you had Primary, Secondary Tertiary configs on your APs (which you may still have).  All it is saying is that the N+1 HA WLC can act as one of these Secondary/Tertiary WLCs, much like a WLC you had licenesed for 250 or 500 APs could do previously.

In the past you would use, lets say a 250 WLC AP as this backup WLC.  Many people were frustrated that they had to have a $60,000 WLC just sitting there "waiting for something to fail".  But that's what it did.  If a WLC failed, lets say one with 100 APs, this backup WLC would take on the APs and use 100 of it's 250 AP license count.  If additional WLCs failed, the process continued until this backup WLC was filled.

The idea of using the HA-SKU in an N+1 is that while yes, you don't get the 1:1 AP SSO configuration, you are getting more bang for your buck in that this WLC can sit as a backup (as it did in the past) but it can accept up to the maximum it's hardware can handle in terms of AP count, not only what it was permanently licensed for.  Rather than spending $100,00 on a 500 AP count WLC to backup your 2x250 AP count WLCs, why not look at a $50,000 HA-SKU that can "handle" up to 500 APs.

So given this scenario, this WLC is "backuping up all other WLCs" for whom it is a Secondary/Tertiary WLC backup.

As far as the HA-SKU "licenese", it's not "permanent" per se.  With an HA SKU in N+1 you have a 90 day timer which will then "nag you" (via console) that this HA WLC is not truly intended to permanently house these APs.  The idea is that if the Primary WLC failed, you would get it back online and then move your APs back to where they belong and return the HA N+1 WLC back to 0 APs.

New Member

WLC 5508 7.4.X - N+1

I understand. But how can one 5508 make the backup for all other controller. On 5508 you can configure only 500 ap group and for redundancy purpose you must use the same ap group name and the same wlan id otherwise lose the local vlan (for flex connect local switching).

How can do that ? if the other controllers will have more than 500 ap group !!!

New Member

WLC 5508 7.4.X - N+1

then in the previously release the temporary licenses were not reactivated and now with 7.4 you can re-activate each time (after a failure) .. I understand correctly?

Hall of Fame Super Silver

WLC 5508 7.4.X - N+1

If you purchase a AIR-CT5508-HA-K9, that will allow you to configure HA in either an AP SSO or N+1.  You don't need to purchase any license and the unit will support up to the max of 500 AP's.  Some customers want to have a low cost solution and to have more than one redundant backup solution.  This is when you can have one licenses WLC and multiple

AIR-CT5508-HA-K9 in an N+1 design.  The license will show up as an eval, but after the 90 days, the unit still functions to allow you to backup the full 500 AP.

Thanks,

Scott

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

-Scott
*** Please rate helpful posts ***
New Member

WLC 5508 7.4.X - N+1

I know on the forum and I believe you, but on HA with AP SSO enabled this is equally true ??

or after 90 day the countdown and the trial expiry and the unit don't work ...

Hall of Fame Super Silver

WLC 5508 7.4.X - N+1

It still works.

Thanks,

Scott

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

-Scott
*** Please rate helpful posts ***
New Member

WLC 5508 7.4.X - N+1

from 7.4 to 7.6 release ? right ? or don't work in 7.4 firmware

Hall of Fame Super Silver

WLC 5508 7.4.X - N+1

On the v7.4 and later with the 5508... yes it will work.

Thanks,

Scott

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

-Scott
*** Please rate helpful posts ***
193
Views
0
Helpful
8
Replies
CreatePlease to create content