Query regarding HA

[diancious]

Hi,

I have a scenario in which I have an Existing WLC in place. The task is to install another WLC which is going to be in HA with this WLC.

The new WLC would be in a different geographical location than the Primary (Existing) WLC.

As per my understanding, the WLCs had to be connected directly in the same premises using the Redundancy port for sync traffic.

Is this configuration possible? If that is the case, would there be any issues related to this design?

Thanks in advance.

[Leo Laohoo]

As per my understanding, the WLCs had to be connected directly in the same premises using the Redundancy port for sync traffic.

Is this configuration possible? If that is the case, would there be any issues related to this design?

This is possible but won't be easy to achieve.  The main question is this:  Do you have a direct Layer 2 connection between the two Redundant Ports?  

I've seen this setup when the two redundant ports are connected using Fibre Optic.  It was a very painful and expensive exercise because the dark fibre had to be laid (versus the cost of doing CWDM/DWDM) and two media-converter had to to be used.

[diancious]

Direct layer 2 connectivity would not be possible as the distance between both WLCs would be approximately 400-450 kms.

I have read about N+1 type configuration. How reliable would that be?

[Leo Laohoo]

I have read about N+1 type configuration. How reliable would that be?

They are reliable.  But the main question is this: Are you willing to tolerate a delay when the APs failover to the secondary controller?

[diancious]

That is a risk we will have to take because direct connectivity is not possible.

Is there any alternative other than N+1 configuration for this scenario? Both the locations (location where primary WLC is currently present and the location where the new backup WLC would be placed) would be connected via an MPLS link.

[Leo Laohoo]

Does each site have a local authentication server?  If they do, then you could try using FlexConnect/H-REAP.

[diancious]

Ok. Thanks Leo.