When updating weight, check quorum state.

MISC check can update the weight of a real server. This can lead to a
change in quorum state.

We factor out quorum handling from perform_svr_state() into a new
function update_quorum_state() that will check if the quorum state
changed and if yes, update sorry server status, exec quorum commands
and add back or remove alive real servers (with existing function
perform_quorum_state()).

This patch is mostly cut'n'paste and adding a call to
update_quorum_state() in update_svr_wgt(). We also make
perform_svr_state() and update_quorum_state() almost symmetric.

diff --git a/keepalived/check/ipwrapper.c b/keepalived/check/ipwrapper.c
index c2431bc..9bad5ad 100644 (file)
--- a/keepalived/check/ipwrapper.c
+++ b/keepalived/check/ipwrapper.c
@@ -237,6 +237,89 @@ perform_quorum_state(virtual_server *vs, int add)
        }
 }
 
+/* set quorum state depending on current weight of real servers */
+void
+update_quorum_state(virtual_server * vs)
+{
+       char rsip[16], vsip[16];
+
+       /* If we have just gained quorum, it's time to consider notify_up. */
+       if (vs->quorum_state == DOWN
+           && weigh_live_realservers(vs) >= vs->quorum + vs->hysteresis) {
+               vs->quorum_state = UP;
+               log_message(LOG_INFO, "Gained quorum %lu+%lu=%lu <= %u for VS [%s:%d]"
+                           , vs->quorum
+                           , vs->hysteresis
+                           , vs->quorum + vs->hysteresis
+                           , weigh_live_realservers(vs)
+                           , (vs->vsgname) ? vs->vsgname : inet_ntoa2(SVR_IP(vs), vsip)
+                           , ntohs(SVR_PORT(vs)));
+               if (vs->s_svr && ISALIVE(vs->s_svr)) {
+                       log_message(LOG_INFO,
+                                   "Removing sorry server [%s:%d] from VS [%s:%d]",
+                                   inet_ntoa2(SVR_IP(vs->s_svr), rsip)
+                                   , ntohs(SVR_PORT(vs->s_svr))
+                                   , (vs->vsgname) ? vs->vsgname : inet_ntoa2(SVR_IP(vs), vsip)
+                                   , ntohs(SVR_PORT(vs)));
+
+                       ipvs_cmd(LVS_CMD_DEL_DEST
+                                , check_data->vs_group
+                                , vs
+                                , vs->s_svr);
+                       vs->s_svr->alive = 0;
+
+                       /* Adding back alive real servers */
+                       perform_quorum_state(vs, 1);
+               }
+               if (vs->quorum_up) {
+                       log_message(LOG_INFO, "Executing [%s] for VS [%s:%d]"
+                                   , vs->quorum_up
+                                   , (vs->vsgname) ? vs->vsgname : inet_ntoa2(SVR_IP(vs), vsip)
+                                   , ntohs(SVR_PORT(vs)));
+                       notify_exec(vs->quorum_up);
+               }
+               return;
+       }
+
+       /* If we have just lost quorum for the VS, we need to consider
+        * VS notify_down and sorry_server cases
+        */
+       if (vs->quorum_state == UP
+           && weigh_live_realservers(vs) < vs->quorum - vs->hysteresis) {
+               vs->quorum_state = DOWN;
+               log_message(LOG_INFO, "Lost quorum %lu-%lu=%lu > %u for VS [%s:%d]"
+                           , vs->quorum
+                           , vs->hysteresis
+                           , vs->quorum - vs->hysteresis
+                           , weigh_live_realservers(vs)
+                           , (vs->vsgname) ? vs->vsgname : inet_ntoa2(SVR_IP(vs), vsip)
+                           , ntohs(SVR_PORT(vs)));
+               if (vs->quorum_down) {
+                       log_message(LOG_INFO, "Executing [%s] for VS [%s:%d]"
+                                   , vs->quorum_down
+                                   , (vs->vsgname) ? vs->vsgname : inet_ntoa2(SVR_IP(vs), vsip)
+                                   , ntohs(SVR_PORT(vs)));
+                       notify_exec(vs->quorum_down);
+               }
+               if (vs->s_svr) {
+                       log_message(LOG_INFO,
+                                   "Adding sorry server [%s:%d] to VS [%s:%d]",
+                                   inet_ntoa2(SVR_IP(vs->s_svr), rsip)
+                                   , ntohs(SVR_PORT(vs->s_svr))
+                                   , (vs->vsgname) ? vs->vsgname : inet_ntoa2(SVR_IP(vs), vsip)
+                                   , ntohs(SVR_PORT(vs)));
+
+                       /* the sorry server is now up in the pool, we flag it alive */
+                       ipvs_cmd(LVS_CMD_ADD_DEST, check_data->vs_group, vs, vs->s_svr);
+                       vs->s_svr->alive = 1;
+
+                       /* Remove remaining alive real servers */
+                       perform_quorum_state(vs, 0);
+               }
+               return;
+       }
+}
+
 /* manipulate add/remove rs according to alive state */
 void
 perform_svr_state(int alive, virtual_server * vs, real_server * rs)
@@ -252,29 +335,6 @@ perform_svr_state(int alive, virtual_server * vs, real_server * rs)
 
        if (!ISALIVE(rs) && alive) {
 
-               /* adding a server to the vs pool, if sorry server is flagged alive,
-                * we remove it from the vs pool.
-                */
-               if (vs->s_svr) {
-                       if (ISALIVE(vs->s_svr) &&
-                           (vs->quorum_state == UP ||
-                            (weigh_live_realservers(vs) + rs->weight >=
-                             vs->quorum + vs->hysteresis))) {
-                               log_message(LOG_INFO,
-                                      "Removing sorry server [%s:%d] from VS [%s:%d]",
-                                      inet_ntoa2(SVR_IP(vs->s_svr), rsip)
-                                      , ntohs(SVR_PORT(vs->s_svr))
-                                      , (vs->vsgname) ? vs->vsgname : inet_ntoa2(SVR_IP(vs), vsip)
-                                      , ntohs(SVR_PORT(vs)));
-
-                               ipvs_cmd(LVS_CMD_DEL_DEST
-                                        , check_data->vs_group
-                                        , vs
-                                        , vs->s_svr);
-                               vs->s_svr->alive = 0;
-                       }
-               }
-
                log_message(LOG_INFO, "%s service [%s:%d] to VS [%s:%d]",
                       (rs->inhibit) ? "Enabling" : "Adding"
                       , inet_ntoa2(SVR_IP(rs), rsip)
@@ -296,29 +356,9 @@ perform_svr_state(int alive, virtual_server * vs, real_server * rs)
                               , ntohs(SVR_PORT(vs)));
                        notify_exec(rs->notify_up);
                }
-               /* If we have just gained quorum, it's time to consider notify_up. */
-               if (vs->quorum_state == DOWN
-                 && weigh_live_realservers(vs) >= vs->quorum + vs->hysteresis) {
-                       vs->quorum_state = UP;
-                       log_message(LOG_INFO, "Gained quorum %lu+%lu=%lu <= %u for VS [%s:%d]"
-                                   , vs->quorum
-                                   , vs->hysteresis
-                                   , vs->quorum + vs->hysteresis
-                                   , weigh_live_realservers(vs)
-                                   , (vs->vsgname) ? vs->vsgname : inet_ntoa2(SVR_IP(vs), vsip)
-                                   , ntohs(SVR_PORT(vs)));
-                       if (vs->s_svr)
-                               /* Adding back alive real servers */
-                               perform_quorum_state(vs, 1);
-                       if (vs->quorum_up) {
-                               log_message(LOG_INFO, "Executing [%s] for VS [%s:%d]"
-                                           , vs->quorum_up
-                                           , (vs->vsgname) ? vs->vsgname : inet_ntoa2(SVR_IP(vs), vsip)
-                                           , ntohs(SVR_PORT(vs)));
-                               notify_exec(vs->quorum_up);
-                       }
-               }
-               return;
+
+               /* We may have gained quorum */
+               update_quorum_state(vs);
        }
 
        if (ISALIVE(rs) && !alive) {
@@ -347,42 +387,8 @@ perform_svr_state(int alive, virtual_server * vs, real_server * rs)
                        notify_exec(rs->notify_down);
                }
 
-               /* If we have just lost quorum for the VS, we need to consider
-                * VS notify_down and sorry_server cases
-                */
-               if (vs->quorum_state == UP
-                   && weigh_live_realservers(vs) < vs->quorum - vs->hysteresis) {
-                       vs->quorum_state = DOWN;
-                       log_message(LOG_INFO, "Lost quorum %lu-%lu=%lu > %u for VS [%s:%d]"
-                                   , vs->quorum
-                                   , vs->hysteresis
-                                   , vs->quorum - vs->hysteresis
-                                   , weigh_live_realservers(vs)
-                                   , (vs->vsgname) ? vs->vsgname : inet_ntoa2(SVR_IP(vs), vsip)
-                                   , ntohs(SVR_PORT(vs)));
-                       if (vs->quorum_down) {
-                               log_message(LOG_INFO, "Executing [%s] for VS [%s:%d]"
-                                           , vs->quorum_down
-                                           , (vs->vsgname) ? vs->vsgname : inet_ntoa2(SVR_IP(vs), vsip)
-                                           , ntohs(SVR_PORT(vs)));
-                               notify_exec(vs->quorum_down);
-                       }
-                       if (vs->s_svr) {
-                               log_message(LOG_INFO,
-                                           "Adding sorry server [%s:%d] to VS [%s:%d]",
-                                           inet_ntoa2(SVR_IP(vs->s_svr), rsip)
-                                           , ntohs(SVR_PORT(vs->s_svr))
-                                           , (vs->vsgname) ? vs->vsgname : inet_ntoa2(SVR_IP(vs), vsip)
-                                           , ntohs(SVR_PORT(vs)));
-
-                               /* the sorry server is now up in the pool, we flag it alive */
-                               ipvs_cmd(LVS_CMD_ADD_DEST, check_data->vs_group, vs, vs->s_svr);
-                               vs->s_svr->alive = 1;
-
-                               /* Remove remaining alive real servers */
-                               perform_quorum_state(vs, 0);
-                       }
-               }
+               /* We may have lost quorum */
+               update_quorum_state(vs);
        }
 }
 
@@ -404,11 +410,12 @@ update_svr_wgt(int weight, virtual_server * vs, real_server * rs)
                                 , ntohs(SVR_PORT(vs)));
                rs->weight = weight;
                /*
-                * Have weight change take effect now only if rs is alive.
+                * Have weight change take effect now only if rs is in the pool.
                 * If not, it will take effect later when it becomes alive.
                 */
-               if (ISALIVE(rs))
+               if (rs->set)
                        ipvs_cmd(LVS_CMD_EDIT_DEST, check_data->vs_group, vs, rs);
+               update_quorum_state(vs);
        }
 }