topic Re: HA Between C9800-L-F & C9800-L-C ? in Wireless

HA Between C9800-L-F & C9800-L-C ?

MY_OREO — Tue, 24 May 2022 10:27:20 GMT

can I have HA Between C9800-L-F & C9800-L-C ?

Re: HA Between C9800-L-F & C9800-L-C ?

Flavio Miranda — Tue, 24 May 2022 10:37:29 GMT

The restriction for HA are those below. As in your case, both are physical WLC, you need to worry about this two requirements:

Both devices must run the same version of software.
Both devices must be running in the same Installation Mode (Either Bundle or Install). We recommend using Install mode for WLC.

Restrictions

Prior to enabling HA between two 9800 WLCs ensure these you perform these validations:

Both devices must be of same PID. In case of 9800-CL, ensure the hosting environment (ESXi or KVM or ENCS) is same for both instances.
Both devices must run the same version of software.
Both devices must be running in the same Installation Mode (Either Bundle or Install). We recommend using Install mode for WLC.
Both devices should have redundant IPs in the same subnet. IP address used for redundancy should be unroutable without a gateway present in the subnet.
Both devices must have their own wireless management interface
Wireless management interface of both devices must belong to the same VLAN/subnet.
In case of 9800-CL,
- Verify same CPU, memory and harddisk resources are allocated to both instances.
- Verify VM snapshot is disabled for both instances.
- Both devices must use the same interface number (For example : GigabitEthernet3) for HA

Re: HA Between C9800-L-F & C9800-L-C ?

Ambuj M — Tue, 24 May 2022 12:47:10 GMT

haven’t tried it first hand myself but I Don’t think so you can do HA between the two, look at page 6 of the deployment guide, it appears you need to have same SKU,

https://www.cisco.com/c/dam/en/us/td/docs/wireless/controller/9800/17-1/deployment-guide/c9800-ha-sso-deployment-guide-rel-17-1.pdf

hope this helps

Re: HA Between C9800-L-F & C9800-L-C ?

Arshad Safrulla — Tue, 24 May 2022 13:49:46 GMT

HA has 2 flavors in Cisco WLC's world.

1. AP/Client SSO - WMI will be one IP and stateful switchover for all the connected clients and AP's are suported and between switchover time is minimal. - This is not supported if 2 different WLC SKU's used as highlighted by others.

2. N+1 HA - There will be 2 WMI's and AP's needs to primed to learn both WMI IP's. There are lot of prerequisites to minimize the downtime such as match the WLC image/SP, AP's needs to be configured with Primary and Secondary WLC WMI etc. AP/Clients will not have stateful switchover, and when the AP's cleints move between WLC's during switchover there will be slightly higher time compared to SSO and clients have to reauth in new WLC. This method is supported irrespective of the platform used.Cisco Catalyst 9800 Wireless Controller N+1 High Availability White Paper