MEDIUM: Add DRAIN state and report it on the stats page

Add a DRAIN sub-state for a server which
will be shown on the stats page instead of UP if
its effective weight is zero.

Also, log if a server enters or leaves the DRAIN state
as the result of an agent check.

Signed-off-by: Simon Horman <horms@verge.net.au>

diff --git a/include/proto/server.h b/include/proto/server.h
index 9c1dbf7fb634cd6c8ef3af4c7ec6b07fb9f93469..9cb814470191240f656fd95dc6f0e8ed26fbe123 100644 (file)
--- a/include/proto/server.h
+++ b/include/proto/server.h
@@ -85,6 +85,18 @@ static inline unsigned int server_throttle_rate(struct server *sv)
 const char *server_parse_weight_change_request(struct server *sv,
                                               const char *weight_str);
 
+/*
+ * Update the server's drain state to reflect its user-weight.  This is not
+ * done immediately to allow a discrepancy between the server's user-weight
+ * and drains state to control logging of changes in the drain state.
+ */
+static inline void set_server_drain_state(struct server *s)
+{
+       if (!s->uweight)
+               s->state |= SRV_DRAIN;
+       else
+               s->state &= ~SRV_DRAIN;
+}
 /*
  * Local variables:
  *  c-indent-level: 8

diff --git a/include/types/server.h b/include/types/server.h
index 96c4318fff2105cae2d0c128e57490ac4259a7bf..6b73a3954234125a8c047499fe7af16a4cd5ff9e 100644 (file)
--- a/include/types/server.h
+++ b/include/types/server.h
@@ -52,7 +52,8 @@
 #define SRV_GOINGDOWN  0x0020  /* this server says that it's going down (404) */
 #define SRV_WARMINGUP  0x0040  /* this server is warming up after a failure */
 #define SRV_MAINTAIN   0x0080  /* this server is in maintenance mode */
-/* unused: 0x0100, 0x0200, 0x0400 */
+#define SRV_DRAIN      0x0100  /* this server has been requested to drain its connections */
+/* unused: 0x0200, 0x0400 */
 #define SRV_SEND_PROXY 0x0800  /* this server talks the PROXY protocol */
 #define SRV_NON_STICK  0x1000  /* never add connections allocated to this server to a stick table */
 #define SRV_AGENT_CHECKED  0x2000  /* this server needs to be checked using an agent check.

diff --git a/src/cfgparse.c b/src/cfgparse.c
index 8c289f1e46710b7e06e01664a5b5874cb3de67f9..c87ca4bd0a8e15c5ec03a865b77bf2ef6ce94b37 100644 (file)
--- a/src/cfgparse.c
+++ b/src/cfgparse.c
@@ -4899,6 +4899,9 @@ stats_error_parsing:
                        }
                }
 
+               /* Set initial drain state using now-configured weight */
+               set_server_drain_state(newsrv);
+
                if (do_check) {
                        int ret;
 

diff --git a/src/checks.c b/src/checks.c
index eb8ce81c165362392ee3200a9cccadf55ab589e1..6acdbe69e189b13abf0e7670e73b8ed8e07e483c 100644 (file)
--- a/src/checks.c
+++ b/src/checks.c
@@ -236,7 +236,10 @@ static void set_server_check_status(struct check *check, short status, const cha
 
        if (s->proxy->options2 & PR_O2_LOGHCHKS &&
        (((check->health != 0) && (check->result & SRV_CHK_FAILED)) ||
-           ((check->health != check->rise + check->fall - 1) && (check->result & SRV_CHK_PASSED)) ||
+           (((check->health != check->rise + check->fall - 1) ||
+             (!s->uweight && !(s->state & SRV_DRAIN)) ||
+             (s->uweight && (s->state & SRV_DRAIN))) &&
+            (check->result & SRV_CHK_PASSED)) ||
            ((s->state & SRV_GOINGDOWN) && !(check->result & SRV_CHK_DISABLE)) ||
            (!(s->state & SRV_GOINGDOWN) && (check->result & SRV_CHK_DISABLE)))) {
 
@@ -290,7 +293,7 @@ static void set_server_check_status(struct check *check, short status, const cha
                chunk_appendf(&trash, ", status: %d/%d %s",
                             (state & SRV_RUNNING) ? (health - rise + 1) : (health),
                             (state & SRV_RUNNING) ? (fall) : (rise),
-                            (state & SRV_RUNNING)?"UP":"DOWN");
+                            (state & SRV_RUNNING)?(s->eweight?"UP":"DRAIN"):"DOWN");
 
                Warning("%s.\n", trash.str);
                send_log(s->proxy, LOG_NOTICE, "%s.\n", trash.str);
@@ -1047,6 +1050,7 @@ static void event_srv_chk_r(struct connection *conn)
                }
 
                set_server_check_status(check, status, desc);
+               set_server_drain_state(check->server);
                break;
        }
 

diff --git a/src/dumpstats.c b/src/dumpstats.c
index adac8346fe2616f054a63ccb172543363930281b..b721c5874d08190bf8ea7bec1bb14fc81e26c429 100644 (file)
--- a/src/dumpstats.c
+++ b/src/dumpstats.c
@@ -1112,6 +1112,12 @@ static int stats_sock_parse_request(struct stream_interface *si, char *line)
                                return 1;
 
                        warning = server_parse_weight_change_request(sv, args[3]);
+                       /*
+                        * The user-weight may now be zero and thus
+                        * the server considered to be draining.
+                        * Update the server's drain state as necessary.
+                        */
+                       set_server_drain_state(sv);
                        if (warning) {
                                si->applet.ctx.cli.msg = warning;
                                si->applet.st0 = STAT_CLI_PRINT;
@@ -2124,7 +2130,8 @@ static int stats_dump_li_stats(struct stream_interface *si, struct proxy *px, st
  * from stream interface <si>, stats flags <flags>, and server state <state>.
  * The caller is responsible for clearing the trash if needed. Returns non-zero
  * if it emits anything, zero otherwise. The <state> parameter can take the
- * following values : 0=DOWN, 1=going up, 2=going down, 3=UP, 4,5=NOLB, 6=unchecked.
+ * following values : 0=DOWN, 1=going up, 2=going down, 3=UP, 4,5=NOLB,
+ * 6,7=DRAIN, 8=unchecked.
  */
 static int stats_dump_sv_stats(struct stream_interface *si, struct proxy *px, int flags, struct server *sv, int state)
 {
@@ -2134,19 +2141,21 @@ static int stats_dump_sv_stats(struct stream_interface *si, struct proxy *px, in
        int i;
 
        if (si->applet.ctx.stats.flags & STAT_FMT_HTML) {
-               static char *srv_hlt_st[7] = {
+               static char *srv_hlt_st[9] = {
                        "DOWN",
                        "DN %d/%d &uarr;",
                        "UP %d/%d &darr;",
                        "UP",
                        "NOLB %d/%d &darr;",
                        "NOLB",
+                       "DRAIN %d/%d &darr;",
+                       "DRAIN",
                        "<i>no check</i>"
                };
 
                if ((sv->state & SRV_MAINTAIN) || (ref->state & SRV_MAINTAIN))
                        chunk_appendf(&trash, "<tr class=\"maintain\">");
-               else if (sv->eweight == 0)
+               else if (sv->eweight == 0 && !(sv->state & SRV_DRAIN))
                        chunk_appendf(&trash, "<tr class=\"softstop\">");
                else
                        chunk_appendf(&trash,
@@ -2354,13 +2363,15 @@ static int stats_dump_sv_stats(struct stream_interface *si, struct proxy *px, in
                        chunk_appendf(&trash, "<td class=ac>-</td></tr>\n");
        }
        else { /* CSV mode */
-               static char *srv_hlt_st[7] = {
+               static char *srv_hlt_st[9] = {
                        "DOWN,",
                        "DOWN %d/%d,",
                        "UP %d/%d,",
                        "UP,",
                        "NOLB %d/%d,",
                        "NOLB,",
+                       "DRAIN %d/%d,",
+                       "DRAIN,",
                        "no check,"
                };
 
@@ -2964,7 +2975,7 @@ static int stats_dump_proxy_to_buffer(struct stream_interface *si, struct proxy
 
                        /* FIXME: produce some small strings for "UP/DOWN x/y &#xxxx;" */
                        if (!(svs->state & SRV_CHECKED))
-                               sv_state = 6;
+                               sv_state = 8;
                        else if (svs->state & SRV_RUNNING) {
                                if (svs->check.health == svs->check.rise + svs->check.fall - 1)
                                        sv_state = 3; /* UP */
@@ -2973,6 +2984,8 @@ static int stats_dump_proxy_to_buffer(struct stream_interface *si, struct proxy
 
                                if (svs->state & SRV_GOINGDOWN)
                                        sv_state += 2;
+                               else if (svs->state & SRV_DRAIN)
+                                       sv_state += 4;
                        }
                        else
                                if (svs->check.health)
@@ -3085,14 +3098,18 @@ static void stats_dump_html_head(struct uri_auth *uri)
                      ".active3 {background: #c0ffc0;}\n"
                      ".active4 {background: #ffffa0;}\n"  /* NOLB state shows same as going down */
                      ".active5 {background: #a0e0a0;}\n"  /* NOLB state shows darker than up */
-                     ".active6 {background: #e0e0e0;}\n"
+                     ".active6 {background: #ffffa0;}\n"
+                     ".active7 {background: #cc9900;}\n"
+                     ".active8 {background: #e0e0e0;}\n"
                      ".backup0 {background: #ff9090;}\n"
                      ".backup1 {background: #ff80ff;}\n"
                      ".backup2 {background: #c060ff;}\n"
                      ".backup3 {background: #b0d0ff;}\n"
                      ".backup4 {background: #c060ff;}\n"  /* NOLB state shows same as going down */
                      ".backup5 {background: #90b0e0;}\n"  /* NOLB state shows same as going down */
-                     ".backup6 {background: #e0e0e0;}\n"
+                     ".backup6 {background: #c060ff;}\n"
+                     ".backup7 {background: #cc9900;}\n"
+                     ".backup8 {background: #e0e0e0;}\n"
                      ".maintain        {background: #c07820;}\n"
                      ".softstop        {background: #0067FF;}\n"
                      ".rls      {letter-spacing: 0.2em; margin-right: 1px;}\n" /* right letter spacing (used for grouping digits) */
@@ -3178,7 +3195,9 @@ static void stats_dump_html_info(struct stream_interface *si, struct uri_auth *u
                      "<td class=\"backup1\"></td><td class=\"noborder\">backup DOWN, going up </td>"
                      "</tr><tr>\n"
                      "<td class=\"active0\"></td><td class=\"noborder\">active or backup DOWN &nbsp;</td>"
-                     "<td class=\"active6\"></td><td class=\"noborder\">not checked </td>"
+                     "<td class=\"active7\"></td><td class=\"noborder\">active or backup DRAIN &nbsp;</td>"
+                     "</tr><tr>\n"
+                     "<td class=\"active8\"></td><td class=\"noborder\">not checked </td>"
                      "</tr><tr>\n"
                      "<td class=\"maintain\"></td><td class=\"noborder\" colspan=\"3\">active or backup DOWN for maintenance (MAINT) &nbsp;</td>"
                      "</tr><tr>\n"
@@ -3354,7 +3373,7 @@ static void stats_dump_html_info(struct stream_interface *si, struct uri_auth *u
                        break;
                default:
                        chunk_appendf(&trash,
-                                     "<p><div class=active6>"
+                                     "<p><div class=active8>"
                                      "<a class=lfsb href=\"%s%s%s%s\" title=\"Remove this message\">[X]</a> "
                                      "Unexpected result."
                                      "</div>\n", uri->uri_prefix,