Ceph » RADOS

In an example scenario where we have 5 monitors:

rank_size = 5
mon.a (rank 0)
mon.b (rank 1)
mon.c (rank 2)
mon.d (rank 3)
mon.e (rank 4)

- we shutdown then remove mon.d (rank 3)
- rank_size = 4
- notifty_rank_removed will adjust the rank of mon.e to become rank 3 and erase 3 in `dead_pinging`

- we shutdown then remove mon.e (rank 3)
- rank_size = 3
- notifty_rank_removed will be called but do nothing because rank_size = 3 and the mon.e is rank 3.
- 3 will remain in `dead_pinging` forever.