From 0bbbf98be4eff74218a010a24f5cafe4da7045b6 Mon Sep 17 00:00:00 2001 From: Nick Mathewson Date: Thu, 28 Dec 2006 21:29:37 +0000 Subject: [PATCH] r11727@Kushana: nickm | 2006-12-28 16:27:17 -0500 If we only have a single nameserver, raise the threshold to decide that the nameserver is dead. (Another fumbling attempt to do something about bug 326.) svn:r9203 --- ChangeLog | 4 +++- doc/TODO | 11 +++++------ src/or/dns.c | 14 +++++++++++--- 3 files changed, 19 insertions(+), 10 deletions(-) diff --git a/ChangeLog b/ChangeLog index ef96db2dbd..28eaeec44f 100644 --- a/ChangeLog +++ b/ChangeLog @@ -122,7 +122,9 @@ Changes in version 0.1.2.5-xxxx - 200?-??-?? - Removed the supposedly misleading error message mentioned in Bug #294. Patch from Matt Edman. - Stop warning when a single nameserver fails: only warn when _all_ of - our nameservers have failed. (Part of a solution to bug #326.) + our nameservers have failed. (Bug #326.) + - When we only have one nameserver, raise the threshold for deciding that + the nameserver is dead. (Also bug #326) o Controller features: - Have GETINFO dir/status/* work on hosts with DirPort disabled. diff --git a/doc/TODO b/doc/TODO index aa08028af5..8ea356ee31 100644 --- a/doc/TODO +++ b/doc/TODO @@ -113,18 +113,17 @@ N - DNS improvements o Bug 363: Warn and die if we can't find a nameserver and we're running a server; don't fall back to 127.0.0.1. o Re-check dns when we change IP addresses, rather than every 12 hours - . Bug 326: Give fewer error messages from nameservers. + o Bug 326: Give fewer error messages from nameservers. o Only warn when _all_ nameservers are down; otherwise info. - - Increase timeout; what's industry standard? - - Alternatively, raise timeout when nameserver dies but comes back + D Increase timeout; what's industry standard? + D Alternatively, raise timeout when nameserver dies but comes back quickly? - - Don't believe that our sole nameserver is dead? or, not until more + o Don't believe that our sole nameserver is dead? or, not until more failures than it would take to think one of several nameservers was dead? - - easy: adjust global_max_nameserver_timeout / global_timeout. X Possibly, don't warn until second retry of a nameserver gets no answer? - - warn if all of your nameservers go down and stay down for like + X warn if all of your nameservers go down and stay down for like 5 minutes. R o Take out the '5 second' timeout from the socks detach schedule. diff --git a/src/or/dns.c b/src/or/dns.c index ca1d60c5bd..212068d4bc 100644 --- a/src/or/dns.c +++ b/src/or/dns.c @@ -216,7 +216,7 @@ dns_reset(void) resolv_conf_mtime = 0; } else { if (configure_nameservers(0) < 0) - /* XXXX */ + /* XXXX012 */ return; } #else @@ -651,7 +651,7 @@ dns_resolve(edge_connection_t *exitconn, or_circuit_t *oncirc) log_debug(LD_EXIT,"Connection (fd %d) found cached error for %s", exitconn->_base.s, escaped_safe_str(exitconn->_base.address)); - /* XXXX send back indication of failure for connect case? -NM*/ + /* XXXX012 send back indication of failure for connect case? -NM*/ if (is_resolve) send_resolved_cell(exitconn, oncirc, RESOLVED_TYPE_ERROR); circ = circuit_get_by_edge_conn(exitconn); @@ -853,7 +853,7 @@ add_answer_to_cache(const char *address, int is_reverse, uint32_t addr, if (outcome == DNS_RESOLVE_FAILED_TRANSIENT) return; - /* XXX This is dumb, but it seems to workaround a bug I can't find. We + /* XXXX012 This is dumb, but it seems to workaround a bug I can't find. We * should nail this so we can cache reverse DNS answers. -NM */ if (is_reverse) return; @@ -1525,6 +1525,14 @@ configure_nameservers(int force) } #endif + if (evdns_count_nameservers() == 1) { + evdns_set_option("max-timeouts:", "16", DNS_OPTIONS_ALL); + evdns_set_option("timeout:", "10", DNS_OPTIONS_ALL); + } else { + evdns_set_option("max-timeouts:", "3", DNS_OPTIONS_ALL); + evdns_set_option("timeout:", "5", DNS_OPTIONS_ALL); + } + dns_servers_relaunch_checks(); nameservers_configured = 1;