From: Ben Pfaff Date: Thu, 13 Jun 2013 19:25:39 +0000 (-0700) Subject: ovsdb-server: Preserve remotes across crash and restart. X-Git-Tag: v2.0~607 X-Git-Url: http://git.cascardo.eti.br/?a=commitdiff_plain;h=5f36127ec6022a124c59566a66e62d643a592057;p=cascardo%2Fovs.git ovsdb-server: Preserve remotes across crash and restart. Commit b421d2af0ab (ovsdb-server: Add commands for adding and removing remotes) made it possible to make ovsdb-server connect to OVS managers only after ovs-vswitchd has completed its initial configuration. But this results in an undesirable effect: whenever ovsdb-server crashes, the monitor restarts its, but ovsdb-server can no longer connect to the manager because the remotes were added during runtime and that information is lost during the crash. This commit fixes the problem. Signed-off-by: Ben Pfaff --- diff --git a/ovsdb/ovsdb-server.c b/ovsdb/ovsdb-server.c index 20e19644b..394f5a515 100644 --- a/ovsdb/ovsdb-server.c +++ b/ovsdb/ovsdb-server.c @@ -81,8 +81,14 @@ struct add_remote_aux { struct sset *remotes; struct db *dbs; size_t n_dbs; + FILE *config_tmpfile; }; static unixctl_cb_func ovsdb_server_add_remote; + +struct remove_remote_aux { + struct sset *remotes; + FILE *config_tmpfile; +}; static unixctl_cb_func ovsdb_server_remove_remote; static unixctl_cb_func ovsdb_server_list_remotes; @@ -99,6 +105,9 @@ static void update_remote_status(const struct ovsdb_jsonrpc_server *jsonrpc, const struct sset *remotes, struct db dbs[], size_t n_dbs); +static void save_config(FILE *config_file, const struct sset *); +static void load_config(FILE *config_file, struct sset *); + int main(int argc, char *argv[]) { @@ -112,6 +121,8 @@ main(int argc, char *argv[]) int retval; long long int status_timer = LLONG_MIN; struct add_remote_aux add_remote_aux; + struct remove_remote_aux remove_remote_aux; + FILE *config_tmpfile; struct db *dbs; int n_dbs; @@ -125,8 +136,22 @@ main(int argc, char *argv[]) parse_options(&argc, &argv, &remotes, &unixctl_path, &run_command); + /* Create and initialize 'config_tmpfile' as a temporary file to hold + * ovsdb-server's most basic configuration, and then save our initial + * configuration to it. When --monitor is used, this preserves the effects + * of ovs-appctl commands such as ovsdb-server/add-remote (which saves the + * new configuration) across crashes. */ + config_tmpfile = tmpfile(); + if (!config_tmpfile) { + ovs_fatal(errno, "failed to create temporary file"); + } + save_config(config_tmpfile, &remotes); + daemonize_start(); + /* Load the saved config. */ + load_config(config_tmpfile, &remotes); + n_dbs = MAX(1, argc); dbs = xcalloc(n_dbs + 1, sizeof *dbs); if (argc > 0) { @@ -195,10 +220,15 @@ main(int argc, char *argv[]) add_remote_aux.remotes = &remotes; add_remote_aux.dbs = dbs; add_remote_aux.n_dbs = n_dbs; + add_remote_aux.config_tmpfile = config_tmpfile; unixctl_command_register("ovsdb-server/add-remote", "REMOTE", 1, 1, ovsdb_server_add_remote, &add_remote_aux); + + remove_remote_aux.remotes = &remotes; + remove_remote_aux.config_tmpfile = config_tmpfile; unixctl_command_register("ovsdb-server/remove-remote", "REMOTE", 1, 1, - ovsdb_server_remove_remote, &remotes); + ovsdb_server_remove_remote, &remove_remote_aux); + unixctl_command_register("ovsdb-server/list-remotes", "", 0, 0, ovsdb_server_list_remotes, &remotes); @@ -922,7 +952,9 @@ ovsdb_server_add_remote(struct unixctl_conn *conn, int argc OVS_UNUSED, : parse_db_column(aux->dbs, aux->n_dbs, remote, &db, &table, &column)); if (!retval) { - sset_add(aux->remotes, remote); + if (sset_add(aux->remotes, remote)) { + save_config(aux->config_tmpfile, aux->remotes); + } unixctl_command_reply(conn, NULL); } else { unixctl_command_reply_error(conn, retval); @@ -934,14 +966,15 @@ ovsdb_server_add_remote(struct unixctl_conn *conn, int argc OVS_UNUSED, * that ovsdb-server services. */ static void ovsdb_server_remove_remote(struct unixctl_conn *conn, int argc OVS_UNUSED, - const char *argv[], void *remotes_) + const char *argv[], void *aux_) { - struct sset *remotes = remotes_; + struct remove_remote_aux *aux = aux_; struct sset_node *node; - node = sset_find(remotes, argv[1]); + node = sset_find(aux->remotes, argv[1]); if (node) { - sset_delete(remotes, node); + sset_delete(aux->remotes, node); + save_config(aux->config_tmpfile, aux->remotes); unixctl_command_reply(conn, NULL); } else { unixctl_command_reply_error(conn, "no such remote"); @@ -1092,3 +1125,56 @@ usage(void) leak_checker_usage(); exit(EXIT_SUCCESS); } + +/* Truncates and replaces the contents of 'config_file' by a representation + * of 'remotes'. */ +static void +save_config(FILE *config_file, const struct sset *remotes) +{ + const char *remote; + struct json *json; + char *s; + + if (ftruncate(fileno(config_file), 0) == -1) { + VLOG_FATAL("failed to truncate temporary file (%s)", strerror(errno)); + } + + json = json_array_create_empty(); + SSET_FOR_EACH (remote, remotes) { + json_array_add(json, json_string_create(remote)); + } + s = json_to_string(json, 0); + json_destroy(json); + + if (fseek(config_file, 0, SEEK_SET) != 0 + || fputs(s, config_file) == EOF + || fflush(config_file) == EOF) { + VLOG_FATAL("failed to write temporary file (%s)", strerror(errno)); + } + free(s); +} + +/* Clears and replaces 'remotes' by a configuration read from 'config_file', + * which must have been previously written by save_config(). */ +static void +load_config(FILE *config_file, struct sset *remotes) +{ + struct json *json; + size_t i; + + sset_clear(remotes); + + if (fseek(config_file, 0, SEEK_SET) != 0) { + VLOG_FATAL("seek failed in temporary file (%s)", strerror(errno)); + } + json = json_from_stream(config_file); + if (json->type == JSON_STRING) { + VLOG_FATAL("reading json failed (%s)", json_string(json)); + } + ovs_assert(json->type == JSON_ARRAY); + for (i = 0; i < json->u.array.n; i++) { + const struct json *remote = json->u.array.elems[i]; + sset_add(remotes, json_string(remote)); + } + json_destroy(json); +} diff --git a/tests/ovsdb-server.at b/tests/ovsdb-server.at index 5f73c008d..acb5a44f3 100644 --- a/tests/ovsdb-server.at +++ b/tests/ovsdb-server.at @@ -271,6 +271,51 @@ AT_CHECK([test ! -e socket1]) AT_CHECK([ovs-appctl -t ovsdb-server ovsdb-server/list-remotes]) AT_CLEANUP +AT_SETUP([ovsdb-server/add-remote and remove-remote with --monitor]) +AT_KEYWORDS([ovsdb server positive]) +# Start ovsdb-server, initially with no remotes. +OVS_RUNDIR=`pwd`; export OVS_RUNDIR +OVS_LOGDIR=`pwd`; export OVS_LOGDIR +ordinal_schema > schema +AT_CHECK([ovsdb-tool create db schema], [0], [ignore], [ignore]) +ON_EXIT([kill `cat *.pid`]) +AT_CHECK([ovsdb-server -v -vvlog:off --monitor --detach --no-chdir --pidfile --log-file db]) + +# Add a remote. +AT_CHECK([test ! -e socket1]) +AT_CHECK([ovs-appctl -t ovsdb-server ovsdb-server/add-remote punix:socket1]) +OVS_WAIT_UNTIL([test -S socket1]) +AT_CHECK([ovs-appctl -t ovsdb-server ovsdb-server/list-remotes], + [0], [punix:socket1 +]) + +# Kill the daemon process, making it look like a segfault, +# and wait for a new daemon process to get spawned and for it to +# start listening on 'socket1'. +cp ovsdb-server.pid old.pid +rm socket1 +AT_CHECK([kill -SEGV `cat ovsdb-server.pid`]) +OVS_WAIT_WHILE([kill -0 `cat old.pid`]) +OVS_WAIT_UNTIL( + [test -s ovsdb-server.pid && test `cat ovsdb-server.pid` != `cat old.pid`]) +OVS_WAIT_UNTIL([test -S socket1]) + +# Remove the remote. +AT_CHECK([ovs-appctl -t ovsdb-server ovsdb-server/remove-remote punix:socket1]) +OVS_WAIT_UNTIL([test ! -e socket1]) +AT_CHECK([ovs-appctl -t ovsdb-server ovsdb-server/list-remotes]) + +# Kill the daemon process, making it look like a segfault, +# and wait for a new daemon process to get spawned and make sure that it +# does not listen on 'socket1'. +cp ovsdb-server.pid old.pid +AT_CHECK([kill -SEGV `cat ovsdb-server.pid`]) +OVS_WAIT_WHILE([kill -0 `cat old.pid`]) +OVS_WAIT_UNTIL( + [test -s ovsdb-server.pid && test `cat ovsdb-server.pid` != `cat old.pid`]) +AT_CHECK([test ! -e socket1]) +AT_CLEANUP + AT_SETUP([SSL db: implementation]) AT_KEYWORDS([ovsdb server positive ssl $5]) AT_SKIP_IF([test "$HAVE_OPENSSL" = no])