BUG/MEDIUM: servers: check the queues once enabling a server

Commit 64cc49c ("MAJOR: servers: propagate server status changes
asynchronously.") heavily changed the way the server states are
updated since they became asynchronous. During this change, some
code was lost, which is used to shut down some sessions from a
backup server and to pick pending connections from a proxy once
a server is turned back from maintenance to ready state. The
effect is that when temporarily disabling a server, connections
stay in the backend's queue, and when re-enabling it, they are
not picked and they expire in the backend's queue. Now they're
properly picked again.

This fix must be backported to 1.8.

diff --git a/src/server.c b/src/server.c
index 4498fd878793253fa218a32276ba24979a3ec146..1aedaf88c5a4ae78c9740e7be14f20bf1f790b9d 100644 (file)
--- a/src/server.c
+++ b/src/server.c
@@ -4849,6 +4849,19 @@ void srv_update_status(struct server *s)
                if (prev_srv_count && s->proxy->srv_bck == 0 && s->proxy->srv_act == 0)
                        set_backend_down(s->proxy);
 
+               /* If the server is set with "on-marked-up shutdown-backup-sessions",
+                * and it's not a backup server and its effective weight is > 0,
+                * then it can accept new connections, so we shut down all streams
+                * on all backup servers.
+                */
+               if ((s->onmarkedup & HANA_ONMARKEDUP_SHUTDOWNBACKUPSESSIONS) &&
+                   !(s->flags & SRV_F_BACKUP) && s->next_eweight)
+                       srv_shutdown_backup_streams(s->proxy, SF_ERR_UP);
+
+               /* check if we can handle some connections queued at the proxy. We
+                * will take as many as we can handle.
+                */
+               xferred = pendconn_grab_from_px(s);
        }
        else if (s->next_admin & SRV_ADMF_MAINT) {
                /* remaining in maintenance mode, let's inform precisely about the