Patent ID: 8085687

Claim:
A method, comprising: determining a set of one or more domain identifiers assigned to a switch in a network fabric when the switch joined the network fabric, wherein each of the set of one or more domain identifiers uniquely identifies the switch relative to other switches in the network fabric; composing a message to de-assign the set of one or more domain identifiers from the switch in the network fabric, wherein the message is composed according to a predefined format of a request domain identifier (RDI) message configured to request one or more domain identifiers to be assigned to the switch, the predefined format specifying a valid range of domain identifiers, the message specifying the set of one or more domain identifiers, wherein the set of one or more domain identifiers is within the valid range, and wherein the message further specifies a trigger value outside of the valid range, wherein the RDI message is characterized by absence of the trigger value, and wherein presence of the trigger value in the message indicates that the message is a reverse request domain identifier (RRDI) message configured to request the set of one or more domain identifiers to be de-assigned from the switch; sending the message to a principal switch of the fabric requesting de-assignment of the set of one or more domain identifiers from the switch in the network fabric without a build fabric phase, such as to render the set of one or more domain identifiers available for reassignment to other switches in the network fabric, wherein the build fabric phase comprises reconfiguring one or more switches in the network fabric by flooding the network fabric with build fabric frames; receiving, from the principal switch, a response to the message; upon determining, based on the response indicating that the message contains an invalid domain identifier, that the principal switch does not support return of domain identifiers without a build fabric phase, initiating a build fabric phase to effect removal of the domain identifiers; and upon determining, based on at least one of the response acknowledging the message and the response including an updated list of fabric identifiers reflecting removal of the domain identifiers, that the principal switch supports return of domain identifiers without a build fabric phase, updating a local list of fabric identifiers to effect removal of the domain identifiers without any build fabric phrase.