C9800 configuration in HA SSO

[aleopoldie]

Hello experts,

I have a doubt concerning C9800 in SSO and in the documentation this is not clear.

Do we have to set redundancy IP's in the same subnet as management interface like on standard WLC's (5520 and so on) ? Or can I set a /30 point-to-point subnet that is not part of the network ?

For example :

WLC 1 mgmt IP : 172.16.0.1

WLC 2 mgmt IP : 172.16.0.2

WLC 1 redudancy mgmt IP : 172.16.0.3

WLC 1 redudancy mgmt IP : 172.16.0.4

Because in the documentation they mention "Both devices should have redundant IPs in the same subnet. IP address used for redundancy should be L2 unroutable"

But the subnet 172.16.0.0 in my example is routed for sure... So I am getting confused.

Just for information, I have to configure these C9800 to be a part of SDA fabric, this is not a standard campus installation.

Thank you,

A.

[codha]

Late reply, but here goes.

The C9800 should as best practice be setup as:

• Interface 1 - Device Management (This is for management of the C9800 itself, and for connectivity with DNA-C/Prime)
• Interface 2 - Wireless Management (This is for AP connectivity to WLC)
• Interface 3 - Redundancy/SSO (This is for HA-SSO between members in the cluster)

Interface 3 should be on a separate IP-subnet/VLAN (And perhaps even on separate switching infrastructure) from the other two interfaces. Common is to use any /24-30 subnet in the APIPA IP-block (169.254.0.0/16) for HA SSO connectivity.