Election logic

The following election logic is executed when MIMP packets are exchanged.

1. Calculate master eligibility.

   • Set masterEligible to TRUE if the local tunnel group is operationally up, otherwise FALSE.

   • Set peerMasterEligible to TRUE if the peer’s tunnel group is operationally up, otherwise FALSE.

2. Elect based on eligibility.

   • If masterEligible and not peerMasterEligible, elect self master → DONE.

   • If not masterEligible and peerMasterEligible, elect peer master → DONE.

   • If not masterEligible and not peerMasterEligible, no master → DONE.

3. Apply stickiness rules (mastership tends not to change).

   • If l was ‟acting master” and peer was not ‟acting master”, then elect self master -> DONE.

   • If 1 was not ‟acting master” and peer was ‟acting master”, then elect peer master -> DONE.

   An ‟acting master” is either in MIMP state ‟master” or ‟eligible”.

4. Elect based on priority and number of active ISAs.

   • If my priority is higher than peer, elect self master → DONE.

   • If peer priority is higher than mine, elect peer master → DONE.

   • If I have more active ISA than peer, elect self master → DONE.

   • If peer has more active ISA than me, elect peer master → DONE.

The tie breaker:

• If the local chassis’ MIMP source address is higher than the peer’s, elect self master → DONE.

• Elect peer master → DONE.