topic Re: SD-Access FIB loopback0 change IP in Software-Defined Access (SD-Access)

SD-Access FIB loopback0 change IP

igor-k — Mon, 18 Nov 2024 13:04:43 GMT

Hi,

I have a working location with single 9300X working as FIB - i.e. it runs edge, contorl, border and also embedded WLC functionality.

The fabric is working good. But now I need to change the Loopback0 IP address (due to global network renumbering).

Is there a safe way to change it?

I mean, I can shortly remove the EN|BN|CP functionality, if needed. I just want to avoid wiping out everything and starting the discovery/fabric configuration from scratch.

Any suggestion appreciated!

IGOR

Re: SD-Access FIB loopback0 change IP

Jhonbruce — Wed, 30 Sep 2026 12:50:20 GMT

Loopback0 is the fabric RLOC — it's what the device registers with the map server and what all the LISP overlay signaling keys off, so there isn't a supported way to just renumber it in place while the fabric roles are active. Since you're on Fabric-in-a-Box with all roles on the single 9300X, the supported path is the one you suspected: remove the EN/BN/CP roles from the device in Catalyst Center first (this cleanly withdraws the LISP registrations and underlay entries), then change the Loopback0 IP, and finally re-provision the fabric roles so the new RLOC gets registered with the map server.

No need to wipe the switch — removing and re-adding the roles is enough. Just plan a maintenance window, take a config backup, and make sure no other part of the global network config references the old RLOC before you change it. Also worth confirming the exact procedure against the SD-Access deployment guide for your Catalyst Center version.

Re: SD-Access FIB loopback0 change IP

balaji.bandi — Thu, 01 Oct 2026 07:25:51 GMT

Loopback 0 acts as the device's anchor point for routing (RLOC), its management address for network orchestration, the control plane mapping database identifier, and the anchor for the embedded WLC (eWLC) wireless management interface (WMI)

https://www.cisco.com/c/en/us/support/docs/switches/catalyst-9300-switch/217434-configure-an-non-sda-ewc-switch-to-onboa.html

i suggest the steps as below :

De-provision Wireless (you can move to different WLC controller for time being) - any way switch go down, so AP also go offline, so downtime needed.

Remove Fabric Roles and make changes , and re-provision WLC.