ESRP

ESRP names:

There are restrictions on Extreme Standby Router Protocol (ESRP) names. They cannot contain whitespaces and cannot start with a numeric value.

You cannot enable an ESRP domain:

Before you enable a specific ESRP domain, it must have a domain ID. A domain ID is either a user-configured number or the 802.1Q tag (VLANid) of the tagged master VLAN. The domain ID must be identical on all switches participating in ESRP for that particular domain. If you do not have a domain ID, you cannot enable ESRP on that domain.

Note the following on the interaction of tagging, ESRP, and ESRP domain IDs:

If you have an untagged Master VLAN, you must specify an ESRP domain ID.
If you have a tagged master VLAN, ESRP uses the 802.1Q tag (VLANid) of the master VLAN for the ESRP domain ID. If you do not use the VLANid as the domain ID, you must specify a different domain ID.

You cannot delete the master VLAN from the ESRP domain:

If you attempt to remove the master VLAN before disabling the ESRP domain, you see an error message similar to the following:

ERROR: Failed to delete master vlan for domain "esrp1" ; ESRP is enabled!

If this happens:

Disable the ESRP domain using the disable esrp command.
Remove the master VLAN from the ESRP domain using the configure esrp delete master command.