MEDIUM: dns: Add resolve-opts "ignore-weight"
It was noted in #48 that there are times when a configuration
may use the server-template directive with SRV records and
simultaneously want to control weights using an agent-check or
through the runtime api. This patch adds a new option
"ignore-weight" to the "resolve-opts" directive.
When specified, any weight indicated within an SRV record will
be ignored. This is for both initial resolution and ongoing
resolution.
diff --git a/src/dns.c b/src/dns.c
index 5f9e7ea..6e726bf 100644
--- a/src/dns.c
+++ b/src/dns.c
@@ -537,7 +537,8 @@
HA_SPIN_LOCK(SERVER_LOCK, &srv->lock);
if (srv->srvrq == srvrq && srv->svc_port == item->port &&
item->data_len == srv->hostname_dn_len &&
- !memcmp(srv->hostname_dn, item->target, item->data_len)) {
+ !memcmp(srv->hostname_dn, item->target, item->data_len) &&
+ !srv->dns_opts.ignore_weight) {
int ha_weight;
/* DNS weight range if from 0 to 65535
@@ -589,15 +590,17 @@
!(srv->flags & SRV_F_CHECKPORT))
srv->check.port = item->port;
- /* DNS weight range if from 0 to 65535
- * HAProxy weight is from 0 to 256
- * The rule below ensures that weight 0 is well respected
- * while allowing a "mapping" from DNS weight into HAProxy's one.
- */
- ha_weight = (item->weight + 255) / 256;
+ if (!srv->dns_opts.ignore_weight) {
+ /* DNS weight range if from 0 to 65535
+ * HAProxy weight is from 0 to 256
+ * The rule below ensures that weight 0 is well respected
+ * while allowing a "mapping" from DNS weight into HAProxy's one.
+ */
+ ha_weight = (item->weight + 255) / 256;
- snprintf(weight, sizeof(weight), "%d", ha_weight);
- server_parse_weight_change_request(srv, weight);
+ snprintf(weight, sizeof(weight), "%d", ha_weight);
+ server_parse_weight_change_request(srv, weight);
+ }
HA_SPIN_UNLOCK(SERVER_LOCK, &srv->lock);
}
}
diff --git a/src/server.c b/src/server.c
index 6b74024..ac7ea37 100644
--- a/src/server.c
+++ b/src/server.c
@@ -1796,6 +1796,7 @@
srv->resolvers_id = strdup(src->resolvers_id);
srv->dns_opts.family_prio = src->dns_opts.family_prio;
srv->dns_opts.accept_duplicate_ip = src->dns_opts.accept_duplicate_ip;
+ srv->dns_opts.ignore_weight = src->dns_opts.ignore_weight;
if (srv->dns_opts.family_prio == AF_UNSPEC)
srv->dns_opts.family_prio = AF_INET6;
memcpy(srv->dns_opts.pref_net,
@@ -2451,11 +2452,14 @@
if (!strcmp(p, "allow-dup-ip")) {
newsrv->dns_opts.accept_duplicate_ip = 1;
}
+ else if (!strcmp(p, "ignore-weight")) {
+ newsrv->dns_opts.ignore_weight = 1;
+ }
else if (!strcmp(p, "prevent-dup-ip")) {
newsrv->dns_opts.accept_duplicate_ip = 0;
}
else {
- ha_alert("parsing [%s:%d]: '%s' : unknown resolve-opts option '%s', supported methods are 'allow-dup-ip' and 'prevent-dup-ip'.\n",
+ ha_alert("parsing [%s:%d]: '%s' : unknown resolve-opts option '%s', supported methods are 'allow-dup-ip', 'ignore-weight', and 'prevent-dup-ip'.\n",
file, linenum, args[cur_arg], p);
err_code |= ERR_ALERT | ERR_FATAL;
goto out;