From 2c7284a9a966a7790cb260e89428db5bb2020eef Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Fri, 10 Jun 2016 20:29:32 +0200 Subject: man: document what SIGUSR1 and SIGUSR2 do to resolved --- man/systemd-resolved.service.xml | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) (limited to 'man') diff --git a/man/systemd-resolved.service.xml b/man/systemd-resolved.service.xml index 829729ca09..485f3e9aee 100644 --- a/man/systemd-resolved.service.xml +++ b/man/systemd-resolved.service.xml @@ -145,6 +145,28 @@ + + Signals + + + + SIGUSR1 + + Upon reception of the SIGUSR1 process signal systemd-resolved will dump the + contents of all DNS resource record caches it maintains into the system logs. + + + + SIGUSR2 + + Upon reception of the SIGUSR2 process signal systemd-resolved will flush all + caches it maintains. Note that it should normally not be necessary to request this explicitly – except for + debugging purposes – as systemd-resolved flushes the caches automatically anyway any time + the host's network configuration changes. + + + + See Also -- cgit v1.2.3-54-g00ecf From ba35662fbdde7b90aed6b34c641b4ff0ea740c68 Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Fri, 10 Jun 2016 20:40:30 +0200 Subject: resolved: also add a way to flush all caches via the bus And expose it in "resolve-tool --flush-caches". --- man/systemd-resolve.xml | 6 ++++++ src/resolve/resolve-tool.c | 36 ++++++++++++++++++++++++++++++++++++ src/resolve/resolved-bus.c | 12 ++++++++++++ src/resolve/resolved-manager.c | 15 +++++++++++---- src/resolve/resolved-manager.h | 2 ++ 5 files changed, 67 insertions(+), 4 deletions(-) (limited to 'man') diff --git a/man/systemd-resolve.xml b/man/systemd-resolve.xml index 4b66f836a2..b917ac20a2 100644 --- a/man/systemd-resolve.xml +++ b/man/systemd-resolve.xml @@ -288,6 +288,12 @@ Resets the statistics counters shown in to zero. + + + + Flushes all DNS resource record caches the service maintains locally. + + diff --git a/src/resolve/resolve-tool.c b/src/resolve/resolve-tool.c index 7e145c64c4..bc6dcf04a4 100644 --- a/src/resolve/resolve-tool.c +++ b/src/resolve/resolve-tool.c @@ -66,6 +66,7 @@ static enum { MODE_RESOLVE_TLSA, MODE_STATISTICS, MODE_RESET_STATISTICS, + MODE_FLUSH_CACHES, } arg_mode = MODE_RESOLVE_HOST; static ServiceFamily service_family_from_string(const char *s) { @@ -1037,6 +1038,24 @@ static int reset_statistics(sd_bus *bus) { return 0; } +static int flush_caches(sd_bus *bus) { + _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL; + int r; + + r = sd_bus_call_method(bus, + "org.freedesktop.resolve1", + "/org/freedesktop/resolve1", + "org.freedesktop.resolve1.Manager", + "FlushCaches", + &error, + NULL, + NULL); + if (r < 0) + return log_error_errno(r, "Failed to flush caches: %s", bus_error_message(&error, r)); + + return 0; +} + static void help_protocol_types(void) { if (arg_legend) puts("Known protocol types:"); @@ -1097,6 +1116,7 @@ static void help(void) { " --legend=BOOL Print headers and additional info (default: yes)\n" " --statistics Show resolver statistics\n" " --reset-statistics Reset resolver statistics\n" + " --flush-caches Flush all local DNS caches\n" , program_invocation_short_name); } @@ -1114,6 +1134,7 @@ static int parse_argv(int argc, char *argv[]) { ARG_SEARCH, ARG_STATISTICS, ARG_RESET_STATISTICS, + ARG_FLUSH_CACHES, }; static const struct option options[] = { @@ -1134,6 +1155,7 @@ static int parse_argv(int argc, char *argv[]) { { "search", required_argument, NULL, ARG_SEARCH }, { "statistics", no_argument, NULL, ARG_STATISTICS, }, { "reset-statistics", no_argument, NULL, ARG_RESET_STATISTICS }, + { "flush-caches", no_argument, NULL, ARG_FLUSH_CACHES }, {} }; @@ -1307,6 +1329,10 @@ static int parse_argv(int argc, char *argv[]) { arg_mode = MODE_RESET_STATISTICS; break; + case ARG_FLUSH_CACHES: + arg_mode = MODE_FLUSH_CACHES; + break; + case '?': return -EINVAL; @@ -1473,6 +1499,16 @@ int main(int argc, char **argv) { r = reset_statistics(bus); break; + + case MODE_FLUSH_CACHES: + if (argc > optind) { + log_error("Too many arguments."); + r = -EINVAL; + goto finish; + } + + r = flush_caches(bus); + break; } finish: diff --git a/src/resolve/resolved-bus.c b/src/resolve/resolved-bus.c index 6d4e5746f7..a72a03cfad 100644 --- a/src/resolve/resolved-bus.c +++ b/src/resolve/resolved-bus.c @@ -1535,6 +1535,17 @@ static int bus_method_get_link(sd_bus_message *message, void *userdata, sd_bus_e return sd_bus_reply_method_return(message, "o", p); } +static int bus_method_flush_caches(sd_bus_message *message, void *userdata, sd_bus_error *error) { + Manager *m = userdata; + + assert(message); + assert(m); + + manager_flush_caches(m); + + return sd_bus_reply_method_return(message, NULL); +} + static const sd_bus_vtable resolve_vtable[] = { SD_BUS_VTABLE_START(0), SD_BUS_PROPERTY("LLMNRHostname", "s", NULL, offsetof(Manager, llmnr_hostname), 0), @@ -1550,6 +1561,7 @@ static const sd_bus_vtable resolve_vtable[] = { SD_BUS_METHOD("ResolveRecord", "isqqt", "a(iqqay)t", bus_method_resolve_record, SD_BUS_VTABLE_UNPRIVILEGED), SD_BUS_METHOD("ResolveService", "isssit", "a(qqqsa(iiay)s)aayssst", bus_method_resolve_service, SD_BUS_VTABLE_UNPRIVILEGED), SD_BUS_METHOD("ResetStatistics", NULL, NULL, bus_method_reset_statistics, 0), + SD_BUS_METHOD("FlushCaches", NULL, NULL, bus_method_flush_caches, 0), SD_BUS_METHOD("GetLink", "i", "o", bus_method_get_link, SD_BUS_VTABLE_UNPRIVILEGED), SD_BUS_METHOD("SetLinkDNS", "ia(iay)", NULL, bus_method_set_link_dns_servers, 0), SD_BUS_METHOD("SetLinkDomains", "ia(sb)", NULL, bus_method_set_link_domains, 0), diff --git a/src/resolve/resolved-manager.c b/src/resolve/resolved-manager.c index 6cf75f9183..a46f13b92f 100644 --- a/src/resolve/resolved-manager.c +++ b/src/resolve/resolved-manager.c @@ -468,16 +468,14 @@ static int manager_sigusr1(sd_event_source *s, const struct signalfd_siginfo *si static int manager_sigusr2(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) { Manager *m = userdata; - DnsScope *scope; assert(s); assert(si); assert(m); - LIST_FOREACH(scopes, scope, m->dns_scopes) - dns_cache_flush(&scope->cache); - + manager_flush_caches(m); log_info("Flushed all caches."); + return 0; } @@ -1251,3 +1249,12 @@ bool manager_routable(Manager *m, int family) { return false; } + +void manager_flush_caches(Manager *m) { + DnsScope *scope; + + assert(m); + + LIST_FOREACH(scopes, scope, m->dns_scopes) + dns_cache_flush(&scope->cache); +} diff --git a/src/resolve/resolved-manager.h b/src/resolve/resolved-manager.h index 97f75ace79..ef71202ef9 100644 --- a/src/resolve/resolved-manager.h +++ b/src/resolve/resolved-manager.h @@ -170,3 +170,5 @@ bool manager_dnssec_supported(Manager *m); void manager_dnssec_verdict(Manager *m, DnssecVerdict verdict, const DnsResourceKey *key); bool manager_routable(Manager *m, int family); + +void manager_flush_caches(Manager *m); -- cgit v1.2.3-54-g00ecf