[Sheepdog] [PATCH v2] sheep: fix a network partition issue

[zituan at taobao.com]

From: Yibin Shen <zituan at taobao.com>

In some situation, sheep may disconnected from corosync instantaneously,
at the same time, both sheep and corosync will keep running but
none of them exit, then the disconnected sheep may receive a confchg
message from corosync which notify this sheep has left.
that will lead to a network partition, this patch fix it.

Signed-off-by: Yibin Shen <zituan at taobao.com>
---
 sheep/group.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/sheep/group.c b/sheep/group.c
index e22dabc..ab5a9f0 100644
--- a/sheep/group.c
+++ b/sheep/group.c
@@ -1467,6 +1467,9 @@ static void sd_leave_handler(struct sheepdog_node_list_entry *left,
 	struct work_leave *w = NULL;
 	int i, size;
 
+	if (node_cmp(left, &sys->this_node) == 0)
+		panic("BUG: this node can't be on the left list\n");
+
 	dprintf("leave %s\n", node_to_str(left));
 	for (i = 0; i < nr_members; i++)
 		dprintf("[%x] %s\n", i, node_to_str(members + i));
-- 
1.7.7