backup upstream servers
diff --git a/src/http/ngx_http_upstream.c b/src/http/ngx_http_upstream.c
index bc45674..43f3ada 100644
--- a/src/http/ngx_http_upstream.c
+++ b/src/http/ngx_http_upstream.c
@@ -565,9 +565,11 @@
if (rc == NGX_BUSY) {
ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "no live upstreams");
+ ngx_http_upstream_next(r, u, NGX_HTTP_UPSTREAM_FT_NOLIVE);
+ return;
}
- if (rc == NGX_BUSY || rc == NGX_DECLINED) {
+ if (rc == NGX_DECLINED) {
ngx_http_upstream_next(r, u, NGX_HTTP_UPSTREAM_FT_ERROR);
return;
}
@@ -2153,7 +2155,9 @@
state = NGX_PEER_FAILED;
}
- u->peer.free(&u->peer, u->peer.data, state);
+ if (ft_type != NGX_HTTP_UPSTREAM_FT_NOLIVE) {
+ u->peer.free(&u->peer, u->peer.data, state);
+ }
if (ft_type == NGX_HTTP_UPSTREAM_FT_TIMEOUT) {
ngx_log_error(NGX_LOG_ERR, r->connection->log, NGX_ETIMEDOUT,
@@ -3118,6 +3122,17 @@
continue;
}
+ if (ngx_strncmp(value[i].data, "backup", 6) == 0) {
+
+ if (!(uscf->flags & NGX_HTTP_UPSTREAM_BACKUP)) {
+ goto invalid;
+ }
+
+ us->backup = 1;
+
+ continue;
+ }
+
if (ngx_strncmp(value[i].data, "down", 4) == 0) {
if (!(uscf->flags & NGX_HTTP_UPSTREAM_DOWN)) {
diff --git a/src/http/ngx_http_upstream.h b/src/http/ngx_http_upstream.h
index b3bb1b4..5c77be3 100644
--- a/src/http/ngx_http_upstream.h
+++ b/src/http/ngx_http_upstream.h
@@ -24,6 +24,7 @@
#define NGX_HTTP_UPSTREAM_FT_HTTP_404 0x00000040
#define NGX_HTTP_UPSTREAM_FT_BUSY_LOCK 0x00000080
#define NGX_HTTP_UPSTREAM_FT_MAX_WAITING 0x00000100
+#define NGX_HTTP_UPSTREAM_FT_NOLIVE 0x40000000
#define NGX_HTTP_UPSTREAM_FT_OFF 0x80000000
diff --git a/src/http/ngx_http_upstream_round_robin.c b/src/http/ngx_http_upstream_round_robin.c
index 73896fc..8aecb47 100644
--- a/src/http/ngx_http_upstream_round_robin.c
+++ b/src/http/ngx_http_upstream_round_robin.c
@@ -20,15 +20,20 @@
ngx_url_t u;
ngx_uint_t i, j, n;
ngx_http_upstream_server_t *server;
- ngx_http_upstream_rr_peers_t *peers;
+ ngx_http_upstream_rr_peers_t *peers, *backup;
us->peer.init = ngx_http_upstream_init_round_robin_peer;
if (us->servers) {
- n = 0;
server = us->servers->elts;
+ n = 0;
+
for (i = 0; i < us->servers->nelts; i++) {
+ if (server[i].backup) {
+ continue;
+ }
+
n += server[i].naddrs;
}
@@ -38,6 +43,7 @@
return NGX_ERROR;
}
+ peers->single = (n == 1);
peers->number = n;
peers->name = &us->host;
@@ -45,6 +51,10 @@
for (i = 0; i < us->servers->nelts; i++) {
for (j = 0; j < server[i].naddrs; j++) {
+ if (server[i].backup) {
+ continue;
+ }
+
peers->peer[n].sockaddr = server[i].addrs[j].sockaddr;
peers->peer[n].socklen = server[i].addrs[j].socklen;
peers->peer[n].name = server[i].addrs[j].name;
@@ -59,6 +69,55 @@
us->peer.data = peers;
+ /* backup servers */
+
+ n = 0;
+
+ for (i = 0; i < us->servers->nelts; i++) {
+ if (!server[i].backup) {
+ continue;
+ }
+
+ n += server[i].naddrs;
+ }
+
+ if (n == 0) {
+ return NGX_OK;
+ }
+
+ backup = ngx_pcalloc(cf->pool, sizeof(ngx_http_upstream_rr_peers_t)
+ + sizeof(ngx_http_upstream_rr_peer_t) * (n - 1));
+ if (backup == NULL) {
+ return NGX_ERROR;
+ }
+
+ peers->single = 0;
+ backup->single = 0;
+ backup->number = n;
+ backup->name = &us->host;
+
+ n = 0;
+
+ for (i = 0; i < us->servers->nelts; i++) {
+ for (j = 0; j < server[i].naddrs; j++) {
+ if (!server[i].backup) {
+ continue;
+ }
+
+ backup->peer[n].sockaddr = server[i].addrs[j].sockaddr;
+ backup->peer[n].socklen = server[i].addrs[j].socklen;
+ backup->peer[n].name = server[i].addrs[j].name;
+ backup->peer[n].weight = server[i].weight;
+ backup->peer[n].current_weight = server[i].weight;
+ backup->peer[n].max_fails = server[i].max_fails;
+ backup->peer[n].fail_timeout = server[i].fail_timeout;
+ backup->peer[n].down = server[i].down;
+ n++;
+ }
+ }
+
+ peers->next = backup;
+
return NGX_OK;
}
@@ -95,6 +154,7 @@
return NGX_ERROR;
}
+ peers->single = (n == 1);
peers->number = n;
peers->name = &us->host;
@@ -113,6 +173,8 @@
us->peer.data = peers;
+ /* implicitly defined upstream has no backup servers */
+
return NGX_OK;
}
@@ -171,11 +233,13 @@
{
ngx_http_upstream_rr_peer_data_t *rrp = data;
- time_t now;
- uintptr_t m;
- ngx_uint_t i, n;
- ngx_connection_t *c;
- ngx_http_upstream_rr_peer_t *peer;
+ time_t now;
+ uintptr_t m;
+ ngx_int_t rc;
+ ngx_uint_t i, n;
+ ngx_connection_t *c;
+ ngx_http_upstream_rr_peer_t *peer;
+ ngx_http_upstream_rr_peers_t *peers;
ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0,
"get rr peer, try: %ui", pc->tries);
@@ -207,7 +271,7 @@
pc->cached = 0;
pc->connection = NULL;
- if (rrp->peers->number == 1) {
+ if (rrp->peers->single) {
peer = &rrp->peers->peer[0];
} else {
@@ -319,19 +383,53 @@
/* ngx_unlock_mutex(rrp->peers->mutex); */
+ if (pc->tries == 1 && rrp->peers->next) {
+ pc->tries += rrp->peers->next->number;
+
+ n = rrp->peers->next->number / (8 * sizeof(uintptr_t)) + 1;
+ for (i = 0; i < n; n++) {
+ rrp->tried[i] = 0;
+ }
+ }
+
return NGX_OK;
failed:
- /* all peers failed, mark them as live for quick recovery */
+ peers = rrp->peers;
- for (i = 0; i < rrp->peers->number; i++) {
- rrp->peers->peer[i].fails = 0;
+ if (peers->next) {
+
+ /* ngx_unlock_mutex(peers->mutex); */
+
+ ngx_log_debug0(NGX_LOG_DEBUG_HTTP, pc->log, 0, "backup servers");
+
+ rrp->peers = peers->next;
+ pc->tries = rrp->peers->number;
+
+ n = rrp->peers->number / (8 * sizeof(uintptr_t)) + 1;
+ for (i = 0; i < n; n++) {
+ rrp->tried[i] = 0;
+ }
+
+ rc = ngx_http_upstream_get_round_robin_peer(pc, rrp);
+
+ if (rc != NGX_BUSY) {
+ return rc;
+ }
+
+ /* ngx_lock_mutex(peers->mutex); */
}
- /* ngx_unlock_mutex(rrp->peers->mutex); */
+ /* all peers failed, mark them as live for quick recovery */
- pc->name = rrp->peers->name;
+ for (i = 0; i < peers->number; i++) {
+ peers->peer[i].fails = 0;
+ }
+
+ /* ngx_unlock_mutex(peers->mutex); */
+
+ pc->name = peers->name;
return NGX_BUSY;
}
@@ -410,7 +508,7 @@
/* TODO: NGX_PEER_KEEPALIVE */
- if (rrp->peers->number == 1) {
+ if (rrp->peers->single) {
pc->tries = 0;
return;
}
diff --git a/src/http/ngx_http_upstream_round_robin.h b/src/http/ngx_http_upstream_round_robin.h
index 15e6915..a9ab1cf 100644
--- a/src/http/ngx_http_upstream_round_robin.h
+++ b/src/http/ngx_http_upstream_round_robin.h
@@ -35,7 +35,10 @@
} ngx_http_upstream_rr_peer_t;
-typedef struct {
+typedef struct ngx_http_upstream_rr_peers_s ngx_http_upstream_rr_peers_t;
+
+struct ngx_http_upstream_rr_peers_s {
+ ngx_uint_t single; /* unsigned single:1; */
ngx_uint_t number;
ngx_uint_t last_cached;
@@ -44,8 +47,10 @@
ngx_str_t *name;
+ ngx_http_upstream_rr_peers_t *next;
+
ngx_http_upstream_rr_peer_t peer[1];
-} ngx_http_upstream_rr_peers_t;
+};
typedef struct {
