When two members in a 5 member cluster are corrupted, and they
have different hashes, etcd will raise alarm for both members,
but the order isn't guaranteed. But if the two corrupted members
have the same hash, then the order is guaranteed. The leader
always raise alarm in the same order as the member list.
Signed-off-by: Benjamin Wang <wachao@vmware.com>
When the leader detects data inconsistency by comparing hashes,
currently it assumes that the follower is the corrupted member.
It isn't correct, the leader might be the corrupted member as well.
We should depend on quorum to identify the corrupted member.
For example, for 3 member cluster, if 2 members have the same hash,
the the member with different hash is the corrupted one. For 5 member
cluster, if 3 members have the same same, the corrupted member is one
of the left two members; it's also possible that both the left members
are corrupted.
Signed-off-by: Benjamin Wang <wachao@vmware.com>
