Blacklist when 16 queries fail in a row.

git-svn-id: file:///svn/unbound/trunk@1764 be551aaa-1e26-0410-a405-d3ace91eadb9

diff --git a/daemon/cachedump.c b/daemon/cachedump.c
index 01db2f933c3fd486c2e6b548a6c9257b7b1b197b..a4a2794b87c1e1c0943c4b9b8faddff7b5c7e5ee 100644 (file)
--- a/daemon/cachedump.c
+++ b/daemon/cachedump.c
@@ -786,7 +786,7 @@ print_dp_details(SSL* ssl, struct worker* worker, struct delegpt* dp)
 {
        char buf[257];
        struct delegpt_addr* a;
-       int lame, dlame, rlame, rtt, edns_vs, to;
+       int lame, dlame, rlame, rtt, edns_vs, to, lost;
        uint8_t edns_lame_known;
        for(a = dp->target_list; a; a = a->next_target) {
                addr_to_str(&a->addr, a->addrlen, buf, sizeof(buf));
@@ -801,15 +801,15 @@ print_dp_details(SSL* ssl, struct worker* worker, struct delegpt* dp)
                 * lameness won't be reported then */
                if(!infra_get_lame_rtt(worker->env.infra_cache, 
                        &a->addr, a->addrlen, dp->name, dp->namelen,
-                       LDNS_RR_TYPE_A, &lame, &dlame, &rlame, &rtt, 
+                       LDNS_RR_TYPE_A, &lame, &dlame, &rlame, &rtt, &lost,
                        *worker->env.now)) {
                        if(!ssl_printf(ssl, "not in infra cache.\n"))
                                return;
                        continue; /* skip stuff not in infra cache */
                }
-               if(!ssl_printf(ssl, "%s%s%srtt %d msec. ",
+               if(!ssl_printf(ssl, "%s%s%srtt %d msec, %d lost. ",
                        lame?"LAME ":"", dlame?"NoDNSSEC ":"",
-                       rlame?"NoAuthButRecursive ":"", rtt))
+                       rlame?"NoAuthButRecursive ":"", rtt, lost))
                        return;
                if(infra_host(worker->env.infra_cache, &a->addr, a->addrlen,
                        *worker->env.now, &edns_vs, &edns_lame_known, &to)) {

diff --git a/doc/Changelog b/doc/Changelog
index 6890c69c7ddce7a4f4593ec5b4bc368f7fcfa063..73eb08638d2d61721e54c958d9426899e0ed2a6d 100644 (file)
--- a/doc/Changelog
+++ b/doc/Changelog
@@ -1,3 +1,7 @@
+17 August 2009: Wouter
+       - Fix so that servers are only blacklisted if they fail to reply 
+         to 16 queries in a row and the timeout gets above 2 minutes.
+
 14 August 2009: Wouter
        - unbound-control lookup prints out infra cache information, like RTT.
        - Fix bug in DLV lookup reported by Amanda from Secure64.

diff --git a/iterator/iter_utils.c b/iterator/iter_utils.c
index bb529759c9c7ec33819240ca551912f3dd90eefb..765bc6135f6e29c0f38706a31dee1f368e588639 100644 (file)
--- a/iterator/iter_utils.c
+++ b/iterator/iter_utils.c
@@ -151,6 +151,8 @@ iter_apply_cfg(struct iter_env* iter_env, struct config_file* cfg)
  *             values 0 .. 49 are not used, unless that is changed.
  *     USEFUL_SERVER_TOP_TIMEOUT
  *             This value exactly is given for unresponsive blacklisted.
+ *     USEFUL_SERVER_TOP_TIMEOUT+1
+ *             For non-blacklisted servers: huge timeout, but has traffic.
  *     USEFUL_SERVER_TOP_TIMEOUT ..
  *             dnsseclame servers get penalty
  *     USEFUL_SERVER_TOP_TIMEOUT*2 ..
@@ -170,7 +172,7 @@ iter_filter_unsuitable(struct iter_env* iter_env, struct module_env* env,
        uint8_t* name, size_t namelen, uint16_t qtype, uint32_t now, 
        struct delegpt_addr* a)
 {
-       int rtt, lame, reclame, dnsseclame;
+       int rtt, lame, reclame, dnsseclame, lost;
        if(a->bogus)
                return -1; /* address of server is bogus */
        if(donotq_lookup(iter_env->donotq, &a->addr, a->addrlen)) {
@@ -182,7 +184,7 @@ iter_filter_unsuitable(struct iter_env* iter_env, struct module_env* env,
        /* check lameness - need zone , class info */
        if(infra_get_lame_rtt(env->infra_cache, &a->addr, a->addrlen, 
                name, namelen, qtype, &lame, &dnsseclame, &reclame, 
-               &rtt, now)) {
+               &rtt, &lost, now)) {
                log_addr(VERB_ALGO, "servselect", &a->addr, a->addrlen);
                verbose(VERB_ALGO, "   rtt=%d%s%s%s", rtt,
                        lame?" LAME":"",
@@ -190,9 +192,12 @@ iter_filter_unsuitable(struct iter_env* iter_env, struct module_env* env,
                        reclame?" REC_LAME":"");
                if(lame)
                        return -1; /* server is lame */
-               else if(rtt >= USEFUL_SERVER_TOP_TIMEOUT)
+               else if(rtt >= USEFUL_SERVER_TOP_TIMEOUT && 
+                       lost >= USEFUL_SERVER_MAX_LOST)
                                /* server is unresponsive */
                        return USEFUL_SERVER_TOP_TIMEOUT; 
+               else if(rtt >= USEFUL_SERVER_TOP_TIMEOUT) /* not blacklisted*/
+                       return USEFUL_SERVER_TOP_TIMEOUT+1; 
                else if(reclame)
                        return rtt+USEFUL_SERVER_TOP_TIMEOUT*2; /* nonpref */
                else if(dnsseclame )

diff --git a/iterator/iterator.h b/iterator/iterator.h
index c70dadd9c7f9300293dd660fb0402e99751f79e6..b985860e2fcf95088e001e75a0d82cde3fde04b5 100644 (file)
--- a/iterator/iterator.h
+++ b/iterator/iterator.h
@@ -65,6 +65,10 @@ struct iter_priv;
  * Equals RTT_MAX_TIMEOUT
  */
 #define USEFUL_SERVER_TOP_TIMEOUT      120000
+/** Number of lost messages in a row that get a host blacklisted.
+ * With 16, a couple different queries have to time out and no working
+ * queries are happening */
+#define USEFUL_SERVER_MAX_LOST 16
 /** number of retries on outgoing queries */
 #define OUTBOUND_MSG_RETRY 5
 /** RTT band, within this amount from the best, servers are chosen randomly.

diff --git a/services/cache/infra.c b/services/cache/infra.c
index f6ecb40a4dd648377760fa9d3673f9517ed00ccc..fbc52549a7d6b1085215fb9b1780b915f29ed159 100644 (file)
--- a/services/cache/infra.c
+++ b/services/cache/infra.c
@@ -219,6 +219,7 @@ new_host_entry(struct infra_cache* infra, struct sockaddr_storage* addr,
        data->lameness = NULL;
        data->edns_version = 0;
        data->edns_lame_known = 0;
+       data->num_timeouts = 0;
        rtt_init(&data->rtt);
        return &key->entry;
 }
@@ -471,9 +472,14 @@ infra_rtt_update(struct infra_cache* infra,
        /* have an entry, update the rtt, and the ttl */
        data = (struct infra_host_data*)e->data;
        data->ttl = timenow + infra->host_ttl;
-       if(roundtrip == -1)
+       if(roundtrip == -1) {
                rtt_lost(&data->rtt, orig_rtt);
-       else    rtt_update(&data->rtt, roundtrip);
+               if(data->num_timeouts<255)
+                       data->num_timeouts++; 
+       } else {
+               rtt_update(&data->rtt, roundtrip);
+               data->num_timeouts = 0;
+       }
        if(data->rtt.rto > 0)
                rto = data->rtt.rto;
 
@@ -513,7 +519,8 @@ int
 infra_get_lame_rtt(struct infra_cache* infra,
         struct sockaddr_storage* addr, socklen_t addrlen,
         uint8_t* name, size_t namelen, uint16_t qtype, 
-       int* lame, int* dnsseclame, int* reclame, int* rtt, uint32_t timenow)
+       int* lame, int* dnsseclame, int* reclame, int* rtt, int* lost,
+       uint32_t timenow)
 {
        struct infra_host_data* host;
        struct lruhash_entry* e = infra_lookup_host_nottl(infra, addr, 
@@ -523,6 +530,7 @@ infra_get_lame_rtt(struct infra_cache* infra,
                return 0;
        host = (struct infra_host_data*)e->data;
        *rtt = rtt_unclamped(&host->rtt);
+       *lost = (int)host->num_timeouts;
        /* check lameness first, if so, ttl on host does not matter anymore */
        if(infra_lookup_lame(host, name, namelen, timenow, 
                &dlm, &rlm, &alm, &olm)) {

diff --git a/services/cache/infra.h b/services/cache/infra.h
index fa693cf4e08ec68dac72b30372e2535b16090999..e6fc3cda20e7c192eeda43f365363205160e7538 100644 (file)
--- a/services/cache/infra.h
+++ b/services/cache/infra.h
@@ -74,6 +74,8 @@ struct infra_host_data {
         * EDNS lame is when EDNS queries or replies are dropped, 
         * and cause a timeout */
        uint8_t edns_lame_known;
+       /** Number of consequtive timeouts; reset when reply arrives OK. */
+       uint8_t num_timeouts;
 };
 
 /**
@@ -270,13 +272,16 @@ int infra_edns_update(struct infra_cache* infra,
  * @param reclame: if function returns true, this is if it is recursion lame.
  * @param rtt: if function returns true, this returns avg rtt of the server.
  *     The rtt value is unclamped and reflects recent timeouts.
+ * @param lost: number of queries lost in a row.  Reset to 0 when an answer
+ *     gets back.  Gives a connectivity number.
  * @param timenow: what time it is now.
  * @return if found in cache, or false if not (or TTL bad).
  */
 int infra_get_lame_rtt(struct infra_cache* infra,
         struct sockaddr_storage* addr, socklen_t addrlen, 
        uint8_t* name, size_t namelen, uint16_t qtype, 
-       int* lame, int* dnsseclame, int* reclame, int* rtt, uint32_t timenow);
+       int* lame, int* dnsseclame, int* reclame, int* rtt, int* lost,
+       uint32_t timenow);
 
 /**
  * Get memory used by the infra cache.