+* Mon May 23 2005 Brendan O'Dea <bod@optusnet.com.au> 2.0.21
+- Cluster changes from Michael, intended to prevent a stray master
+ from trashing a cluster:
+ + Ignore heartbeats from peers claiming to be the master before the
+ timeout on the old master has expired.
+ + A master receiving a stray heartbeat sends a unicast HB back, which
+ should cause the rogue to die due to the tie-breaker code.
+ + Keep probing the master for late heartbeats.
+ + Drop BGP as soon as we become master with the minumum required peers.
+ + Any PING seen from a master forces an election (rather than just
+ where basetime is zero).
+ + A slave which receives a LASTSEEN message (presumably a restarted
+ master) sends back new message type, C_MASTER which indicates the
+ address of the current master.
+- New config option: cluster_master_min_adv which determines the minimum
+ number of up to date slaves required before the master will drop
+ routes.
+