Employ a Phased Approach
Reduce network impact by applying the password and clearing sessions on fabric links in a phased manner.
When an updated MD5 password is being applied on fabric links during fabric
configuration, you can reduce network impact by applying the password and clearing
sessions on fabric links in a phased manner. First gather a list of neighbor
sessions on each device. Then, one device at a time, apply
md5-password and clear a
single peering. Application of password and clearing of the neighbor session is done
on both ends of the peering session simultaneously. When the session is established,
the MD5 password is applied on the next peering session. When all the neighbor
sessions on the device are updated, it will move to the next device.
After you clear the session, it takes 10 seconds for the new session to be established. Before applying the new MD5 password, the session states are determined. After applying the password and clearing the session on both ends of the peering session, the session state is checked again. Only when the state matches with the previous (pre-password update) state on the session, or is better than the previous state (for example, previously the session was not established and the current state is established), it will move to updating the next neighbor session.
NoteThe phased application of clearing the session and checking the state is performed only when the password is updated on a configured fabric and is not applicable during the configuration of a new fabric. Because the neighbor sessions are created for the first time during configuration of a new fabric with the MD5 password, there is no need to clear sessions.