diff --git a/CHANGES b/CHANGES index 6c037b2d1f..60d25f9c9c 100644 --- a/CHANGES +++ b/CHANGES @@ -1,3 +1,7 @@ +4021. [bug] Adjust max-recursion-queries to accommodate + the need for more queries when the cache is + empty. [RT #38104] + 4020. [bug] Change 3736 broke nsupdate's SOA MNAME discovery resulting in updates being sent to the wrong server. [RT #37925] diff --git a/bin/named/config.c b/bin/named/config.c index 6c7fe19fb5..de685e9b04 100644 --- a/bin/named/config.c +++ b/bin/named/config.c @@ -175,7 +175,7 @@ options {\n\ clients-per-query 10;\n\ max-clients-per-query 100;\n\ max-recursion-depth 7;\n\ - max-recursion-queries 50;\n\ + max-recursion-queries 75;\n\ zero-no-soa-ttl-cache no;\n\ nsec3-test-zone no;\n\ allow-new-zones no;\n\ diff --git a/bin/tests/system/reclimit/ns3/named3.conf b/bin/tests/system/reclimit/ns3/named3.conf index 953a6adc30..23d14d8878 100644 --- a/bin/tests/system/reclimit/ns3/named3.conf +++ b/bin/tests/system/reclimit/ns3/named3.conf @@ -27,6 +27,7 @@ options { listen-on-v6 { none; }; servfail-ttl 0; max-recursion-depth 100; + max-recursion-queries 50; }; key rndc_key { diff --git a/doc/arm/Bv9ARM-book.xml b/doc/arm/Bv9ARM-book.xml index 398a68175b..b459d6a04d 100644 --- a/doc/arm/Bv9ARM-book.xml +++ b/doc/arm/Bv9ARM-book.xml @@ -9123,8 +9123,10 @@ avoid-v6-udp-ports { 40000; range 50000 60000; }; Sets the maximum number of iterative queries that may be sent while servicing a recursive query. If more queries are sent, the recursive query - is terminated and returns SERVFAIL. The default - is 50. + is terminated and returns SERVFAIL. Queries to + look up top level comains such as "com" and "net" + and the DNS root zone are exempt from this limitation. + The default is 75. diff --git a/doc/arm/notes.xml b/doc/arm/notes.xml index bb0c5df039..770ab73d5d 100644 --- a/doc/arm/notes.xml +++ b/doc/arm/notes.xml @@ -423,6 +423,13 @@ rather than the SOA MNAME server when sending the UPDATE. + + + Adjusted max-recursion-queries to accommodate the smaller + initial packet sizes used in BIND 9.10 and higher when + contacting authoritative servers for the first time. + + diff --git a/lib/dns/adb.c b/lib/dns/adb.c index 2a45dadae4..51bac51f4c 100644 --- a/lib/dns/adb.c +++ b/lib/dns/adb.c @@ -3893,11 +3893,11 @@ fetch_callback(isc_task_t *task, isc_event_t *ev) { goto out; /* XXXMLG Don't pound on bad servers. */ if (address_type == DNS_ADBFIND_INET) { - name->expire_v4 = ISC_MIN(name->expire_v4, now + 300); + name->expire_v4 = ISC_MIN(name->expire_v4, now + 10); name->fetch_err = FIND_ERR_FAILURE; inc_stats(adb, dns_resstatscounter_gluefetchv4fail); } else { - name->expire_v6 = ISC_MIN(name->expire_v6, now + 300); + name->expire_v6 = ISC_MIN(name->expire_v6, now + 10); name->fetch6_err = FIND_ERR_FAILURE; inc_stats(adb, dns_resstatscounter_gluefetchv6fail); } diff --git a/lib/dns/resolver.c b/lib/dns/resolver.c index b0f62c2e9c..b6734f8fae 100644 --- a/lib/dns/resolver.c +++ b/lib/dns/resolver.c @@ -164,7 +164,7 @@ /* The default maximum number of iterative queries to allow before giving up. */ #ifndef DEFAULT_MAX_QUERIES -#define DEFAULT_MAX_QUERIES 50 +#define DEFAULT_MAX_QUERIES 75 #endif /*% @@ -3416,6 +3416,16 @@ fctx_try(fetchctx_t *fctx, isc_boolean_t retrying, isc_boolean_t badcache) { REQUIRE(!ADDRWAIT(fctx)); + /* We've already exceeded maximum query count */ + if (isc_counter_used(fctx->qc) > fctx->res->maxqueries) { + isc_log_write(dns_lctx, DNS_LOGCATEGORY_RESOLVER, + DNS_LOGMODULE_RESOLVER, ISC_LOG_DEBUG(3), + "exceeded max queries resolving '%s'", + fctx->info); + fctx_done(fctx, DNS_R_SERVFAIL, __LINE__); + return; + } + addrinfo = fctx_nextaddress(fctx); if (addrinfo == NULL) { /* @@ -3453,14 +3463,16 @@ fctx_try(fetchctx_t *fctx, isc_boolean_t retrying, isc_boolean_t badcache) { } } - result = isc_counter_increment(fctx->qc); - if (result != ISC_R_SUCCESS) { - isc_log_write(dns_lctx, DNS_LOGCATEGORY_RESOLVER, - DNS_LOGMODULE_RESOLVER, ISC_LOG_DEBUG(3), - "exceeded max queries resolving '%s'", - fctx->info); - fctx_done(fctx, DNS_R_SERVFAIL, __LINE__); - return; + if (dns_name_countlabels(&fctx->domain) > 2) { + result = isc_counter_increment(fctx->qc); + if (result != ISC_R_SUCCESS) { + isc_log_write(dns_lctx, DNS_LOGCATEGORY_RESOLVER, + DNS_LOGMODULE_RESOLVER, ISC_LOG_DEBUG(3), + "exceeded max queries resolving '%s'", + fctx->info); + fctx_done(fctx, DNS_R_SERVFAIL, __LINE__); + return; + } } result = fctx_query(fctx, addrinfo, fctx->options);