X-Git-Url: https://git.saurik.com/redis.git/blobdiff_plain/45029d37cb7fe589bdfd9a08dd5a3afd611ad57e..3d1391272aa46aa3a52a700f6b1ef0a47d4dcda9:/src/replication.c diff --git a/src/replication.c b/src/replication.c index 8090a27a..720cd4c1 100644 --- a/src/replication.c +++ b/src/replication.c @@ -1,8 +1,40 @@ +/* Asynchronous replication implementation. + * + * Copyright (c) 2009-2012, Salvatore Sanfilippo <antirez at gmail dot com> + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * * Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * * Neither the name of Redis nor the names of its contributors may be used + * to endorse or promote products derived from this software without + * specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + + #include "redis.h" #include <sys/time.h> #include <unistd.h> #include <fcntl.h> +#include <sys/socket.h> #include <sys/stat.h> /* ---------------------------------- MASTER -------------------------------- */ @@ -25,24 +57,15 @@ void replicationFeedSlaves(list *slaves, int dictid, robj **argv, int argc) { if (slave->slaveseldb != dictid) { robj *selectcmd; - switch(dictid) { - case 0: selectcmd = shared.select0; break; - case 1: selectcmd = shared.select1; break; - case 2: selectcmd = shared.select2; break; - case 3: selectcmd = shared.select3; break; - case 4: selectcmd = shared.select4; break; - case 5: selectcmd = shared.select5; break; - case 6: selectcmd = shared.select6; break; - case 7: selectcmd = shared.select7; break; - case 8: selectcmd = shared.select8; break; - case 9: selectcmd = shared.select9; break; - default: + if (dictid >= 0 && dictid < REDIS_SHARED_SELECT_CMDS) { + selectcmd = shared.select[dictid]; + incrRefCount(selectcmd); + } else { selectcmd = createObject(REDIS_STRING, sdscatprintf(sdsempty(),"select %d\r\n",dictid)); - selectcmd->refcount = 0; - break; } addReply(slave,selectcmd); + decrRefCount(selectcmd); slave->slaveseldb = dictid; } addReplyMultiBulkLen(slave,argc); @@ -50,17 +73,25 @@ void replicationFeedSlaves(list *slaves, int dictid, robj **argv, int argc) { } } -void replicationFeedMonitors(list *monitors, int dictid, robj **argv, int argc) { +void replicationFeedMonitors(redisClient *c, list *monitors, int dictid, robj **argv, int argc) { listNode *ln; listIter li; - int j; + int j, port; sds cmdrepr = sdsnew("+"); robj *cmdobj; + char ip[32]; struct timeval tv; gettimeofday(&tv,NULL); cmdrepr = sdscatprintf(cmdrepr,"%ld.%06ld ",(long)tv.tv_sec,(long)tv.tv_usec); - if (dictid != 0) cmdrepr = sdscatprintf(cmdrepr,"(db %d) ", dictid); + if (c->flags & REDIS_LUA_CLIENT) { + cmdrepr = sdscatprintf(cmdrepr,"[%d lua] ",dictid); + } else if (c->flags & REDIS_UNIX_SOCKET) { + cmdrepr = sdscatprintf(cmdrepr,"[%d unix:%s] ",dictid,server.unixsocket); + } else { + anetPeerToString(c->fd,ip,&port); + cmdrepr = sdscatprintf(cmdrepr,"[%d %s:%d] ",dictid,ip,port); + } for (j = 0; j < argc; j++) { if (argv[j]->encoding == REDIS_ENCODING_INT) { @@ -89,7 +120,7 @@ void syncCommand(redisClient *c) { /* Refuse SYNC requests if we are a slave but the link with our master * is not ok... */ - if (server.masterhost && server.replstate != REDIS_REPL_CONNECTED) { + if (server.masterhost && server.repl_state != REDIS_REPL_CONNECTED) { addReplyError(c,"Can't SYNC while not connected with my master"); return; } @@ -106,7 +137,7 @@ void syncCommand(redisClient *c) { redisLog(REDIS_NOTICE,"Slave ask for synchronization"); /* Here we need to check if there is a background saving operation * in progress, or if it is required to start one */ - if (server.bgsavechildpid != -1) { + if (server.rdb_child_pid != -1) { /* Ok a background save is in progress. Let's check if it is a good * one for replication, i.e. if there is another slave that is * registering differences since the server forked to save */ @@ -122,8 +153,7 @@ void syncCommand(redisClient *c) { if (ln) { /* Perfect, the server is already registering differences for * another slave. Set the right state, and copy the buffer. */ - listRelease(c->reply); - c->reply = listDup(slave->reply); + copyClientOutputBuffer(c,slave); c->replstate = REDIS_REPL_WAIT_BGSAVE_END; redisLog(REDIS_NOTICE,"Waiting for end of BGSAVE for SYNC"); } else { @@ -135,7 +165,7 @@ void syncCommand(redisClient *c) { } else { /* Ok we don't have a BGSAVE in progress, let's start one */ redisLog(REDIS_NOTICE,"Starting BGSAVE for SYNC"); - if (rdbSaveBackground(server.dbfilename) != REDIS_OK) { + if (rdbSaveBackground(server.rdb_filename) != REDIS_OK) { redisLog(REDIS_NOTICE,"Replication failed, can't BGSAVE"); addReplyError(c,"Unable to perform background save"); return; @@ -149,6 +179,46 @@ void syncCommand(redisClient *c) { return; } +/* REPLCONF <option> <value> <option> <value> ... + * This command is used by a slave in order to configure the replication + * process before starting it with the SYNC command. + * + * Currently the only use of this command is to communicate to the master + * what is the listening port of the Slave redis instance, so that the + * master can accurately list slaves and their listening ports in + * the INFO output. + * + * In the future the same command can be used in order to configure + * the replication to initiate an incremental replication instead of a + * full resync. */ +void replconfCommand(redisClient *c) { + int j; + + if ((c->argc % 2) == 0) { + /* Number of arguments must be odd to make sure that every + * option has a corresponding value. */ + addReply(c,shared.syntaxerr); + return; + } + + /* Process every option-value pair. */ + for (j = 1; j < c->argc; j+=2) { + if (!strcasecmp(c->argv[j]->ptr,"listening-port")) { + long port; + + if ((getLongFromObjectOrReply(c,c->argv[j+1], + &port,NULL) != REDIS_OK)) + return; + c->slave_listening_port = port; + } else { + addReplyErrorFormat(c,"Unrecognized REPLCONF option: %s", + (char*)c->argv[j]->ptr); + return; + } + } + addReply(c,shared.ok); +} + void sendBulkToSlave(aeEventLoop *el, int fd, void *privdata, int mask) { redisClient *slave = privdata; REDIS_NOTUSED(el); @@ -198,7 +268,6 @@ void sendBulkToSlave(aeEventLoop *el, int fd, void *privdata, int mask) { freeClient(slave); return; } - addReplySds(slave,sdsempty()); redisLog(REDIS_NOTICE,"Synchronization with slave succeeded"); } } @@ -229,7 +298,7 @@ void updateSlavesWaitingBgsave(int bgsaveerr) { redisLog(REDIS_WARNING,"SYNC failed. BGSAVE child returned an error"); continue; } - if ((slave->repldbfd = open(server.dbfilename,O_RDONLY)) == -1 || + if ((slave->repldbfd = open(server.rdb_filename,O_RDONLY)) == -1 || redis_fstat(slave->repldbfd,&buf) == -1) { freeClient(slave); redisLog(REDIS_WARNING,"SYNC failed. Can't open/stat DB after BGSAVE: %s", strerror(errno)); @@ -246,7 +315,7 @@ void updateSlavesWaitingBgsave(int bgsaveerr) { } } if (startbgsave) { - if (rdbSaveBackground(server.dbfilename) != REDIS_OK) { + if (rdbSaveBackground(server.rdb_filename) != REDIS_OK) { listIter li; listRewind(server.slaves,&li); @@ -265,28 +334,30 @@ void updateSlavesWaitingBgsave(int bgsaveerr) { /* Abort the async download of the bulk dataset while SYNC-ing with master */ void replicationAbortSyncTransfer(void) { - redisAssert(server.replstate == REDIS_REPL_TRANSFER); + redisAssert(server.repl_state == REDIS_REPL_TRANSFER); aeDeleteFileEvent(server.el,server.repl_transfer_s,AE_READABLE); close(server.repl_transfer_s); close(server.repl_transfer_fd); unlink(server.repl_transfer_tmpfile); zfree(server.repl_transfer_tmpfile); - server.replstate = REDIS_REPL_CONNECT; + server.repl_state = REDIS_REPL_CONNECT; } /* Asynchronously read the SYNC payload we receive from a master */ +#define REPL_MAX_WRITTEN_BEFORE_FSYNC (1024*1024*8) /* 8 MB */ void readSyncBulkPayload(aeEventLoop *el, int fd, void *privdata, int mask) { char buf[4096]; ssize_t nread, readlen; + off_t left; REDIS_NOTUSED(el); REDIS_NOTUSED(privdata); REDIS_NOTUSED(mask); - /* If repl_transfer_left == -1 we still have to read the bulk length + /* If repl_transfer_size == -1 we still have to read the bulk length * from the master reply. */ - if (server.repl_transfer_left == -1) { - if (syncReadLine(fd,buf,1024,server.repl_syncio_timeout) == -1) { + if (server.repl_transfer_size == -1) { + if (syncReadLine(fd,buf,1024,server.repl_syncio_timeout*1000) == -1) { redisLog(REDIS_WARNING, "I/O error reading bulk count from MASTER: %s", strerror(errno)); @@ -302,22 +373,22 @@ void readSyncBulkPayload(aeEventLoop *el, int fd, void *privdata, int mask) { /* At this stage just a newline works as a PING in order to take * the connection live. So we refresh our last interaction * timestamp. */ - server.repl_transfer_lastio = time(NULL); + server.repl_transfer_lastio = server.unixtime; return; } else if (buf[0] != '$') { redisLog(REDIS_WARNING,"Bad protocol from MASTER, the first byte is not '$', are you sure the host and port are right?"); goto error; } - server.repl_transfer_left = strtol(buf+1,NULL,10); + server.repl_transfer_size = strtol(buf+1,NULL,10); redisLog(REDIS_NOTICE, "MASTER <-> SLAVE sync: receiving %ld bytes from master", - server.repl_transfer_left); + server.repl_transfer_size); return; } /* Read bulk data */ - readlen = (server.repl_transfer_left < (signed)sizeof(buf)) ? - server.repl_transfer_left : (signed)sizeof(buf); + left = server.repl_transfer_size - server.repl_transfer_read; + readlen = (left < (signed)sizeof(buf)) ? left : (signed)sizeof(buf); nread = read(fd,buf,readlen); if (nread <= 0) { redisLog(REDIS_WARNING,"I/O error trying to sync with MASTER: %s", @@ -325,15 +396,29 @@ void readSyncBulkPayload(aeEventLoop *el, int fd, void *privdata, int mask) { replicationAbortSyncTransfer(); return; } - server.repl_transfer_lastio = time(NULL); + server.repl_transfer_lastio = server.unixtime; if (write(server.repl_transfer_fd,buf,nread) != nread) { - redisLog(REDIS_WARNING,"Write error or short write writing to the DB dump file needed for MASTER <-> SLAVE synchrnonization: %s", strerror(errno)); + redisLog(REDIS_WARNING,"Write error or short write writing to the DB dump file needed for MASTER <-> SLAVE synchronization: %s", strerror(errno)); goto error; } - server.repl_transfer_left -= nread; + server.repl_transfer_read += nread; + + /* Sync data on disk from time to time, otherwise at the end of the transfer + * we may suffer a big delay as the memory buffers are copied into the + * actual disk. */ + if (server.repl_transfer_read >= + server.repl_transfer_last_fsync_off + REPL_MAX_WRITTEN_BEFORE_FSYNC) + { + off_t sync_size = server.repl_transfer_read - + server.repl_transfer_last_fsync_off; + rdb_fsync_range(server.repl_transfer_fd, + server.repl_transfer_last_fsync_off, sync_size); + server.repl_transfer_last_fsync_off += sync_size; + } + /* Check if the transfer is now complete */ - if (server.repl_transfer_left == 0) { - if (rename(server.repl_transfer_tmpfile,server.dbfilename) == -1) { + if (server.repl_transfer_read == server.repl_transfer_size) { + if (rename(server.repl_transfer_tmpfile,server.rdb_filename) == -1) { redisLog(REDIS_WARNING,"Failed trying to rename the temp DB into dump.rdb in MASTER <-> SLAVE synchronization: %s", strerror(errno)); replicationAbortSyncTransfer(); return; @@ -345,7 +430,7 @@ void readSyncBulkPayload(aeEventLoop *el, int fd, void *privdata, int mask) { * rdbLoad() will call the event loop to process events from time to * time for non blocking loading. */ aeDeleteFileEvent(server.el,server.repl_transfer_s,AE_READABLE); - if (rdbLoad(server.dbfilename) != REDIS_OK) { + if (rdbLoad(server.rdb_filename) != REDIS_OK) { redisLog(REDIS_WARNING,"Failed trying to load the MASTER synchronization DB from disk"); replicationAbortSyncTransfer(); return; @@ -356,10 +441,24 @@ void readSyncBulkPayload(aeEventLoop *el, int fd, void *privdata, int mask) { server.master = createClient(server.repl_transfer_s); server.master->flags |= REDIS_MASTER; server.master->authenticated = 1; - server.replstate = REDIS_REPL_CONNECTED; + server.repl_state = REDIS_REPL_CONNECTED; redisLog(REDIS_NOTICE, "MASTER <-> SLAVE sync: Finished with success"); - /* Rewrite the AOF file now that the dataset changed. */ - if (server.appendonly) rewriteAppendOnlyFileBackground(); + /* Restart the AOF subsystem now that we finished the sync. This + * will trigger an AOF rewrite, and when done will start appending + * to the new file. */ + if (server.aof_state != REDIS_AOF_OFF) { + int retry = 10; + + stopAppendOnly(); + while (retry-- && startAppendOnly() == REDIS_ERR) { + redisLog(REDIS_WARNING,"Failed enabling the AOF after successful master synchrnization! Trying it again in one second."); + sleep(1); + } + if (!retry) { + redisLog(REDIS_WARNING,"FATAL: this slave instance finished the synchronization with its master, but the AOF can't be turned on. Exiting now."); + exit(1); + } + } } return; @@ -369,44 +468,152 @@ error: return; } +/* Send a synchronous command to the master. Used to send AUTH and + * REPLCONF commands before starting the replication with SYNC. + * + * On success NULL is returned. + * On error an sds string describing the error is returned. + */ +char *sendSynchronousCommand(int fd, ...) { + va_list ap; + sds cmd = sdsempty(); + char *arg, buf[256]; + + /* Create the command to send to the master, we use simple inline + * protocol for simplicity as currently we only send simple strings. */ + va_start(ap,fd); + while(1) { + arg = va_arg(ap, char*); + if (arg == NULL) break; + + if (sdslen(cmd) != 0) cmd = sdscatlen(cmd," ",1); + cmd = sdscat(cmd,arg); + } + cmd = sdscatlen(cmd,"\r\n",2); + + /* Transfer command to the server. */ + if (syncWrite(fd,cmd,sdslen(cmd),server.repl_syncio_timeout*1000) == -1) { + sdsfree(cmd); + return sdscatprintf(sdsempty(),"Writing to master: %s", + strerror(errno)); + } + sdsfree(cmd); + + /* Read the reply from the server. */ + if (syncReadLine(fd,buf,sizeof(buf),server.repl_syncio_timeout*1000) == -1) + { + return sdscatprintf(sdsempty(),"Reading from master: %s", + strerror(errno)); + } + + /* Check for errors from the server. */ + if (buf[0] != '+') { + return sdscatprintf(sdsempty(),"Error from master: %s", buf); + } + + return NULL; /* No errors. */ +} + void syncWithMaster(aeEventLoop *el, int fd, void *privdata, int mask) { - char buf[1024], tmpfile[256]; + char tmpfile[256], *err; int dfd, maxtries = 5; + int sockerr = 0; + socklen_t errlen = sizeof(sockerr); REDIS_NOTUSED(el); REDIS_NOTUSED(privdata); REDIS_NOTUSED(mask); - redisLog(REDIS_NOTICE,"Non blocking connect for SYNC fired the event."); - /* This event should only be triggered once since it is used to have a - * non-blocking connect(2) to the master. It has been triggered when this - * function is called, so we can delete it. */ - aeDeleteFileEvent(server.el,fd,AE_READABLE|AE_WRITABLE); + /* If this event fired after the user turned the instance into a master + * with SLAVEOF NO ONE we must just return ASAP. */ + if (server.repl_state == REDIS_REPL_NONE) { + close(fd); + return; + } - /* AUTH with the master if required. */ - if(server.masterauth) { - char authcmd[1024]; - size_t authlen; + /* Check for errors in the socket. */ + if (getsockopt(fd, SOL_SOCKET, SO_ERROR, &sockerr, &errlen) == -1) + sockerr = errno; + if (sockerr) { + aeDeleteFileEvent(server.el,fd,AE_READABLE|AE_WRITABLE); + redisLog(REDIS_WARNING,"Error condition on socket for SYNC: %s", + strerror(sockerr)); + goto error; + } - authlen = snprintf(authcmd,sizeof(authcmd),"AUTH %s\r\n",server.masterauth); - if (syncWrite(fd,authcmd,authlen,server.repl_syncio_timeout) == -1) { - redisLog(REDIS_WARNING,"Unable to AUTH to MASTER: %s", + /* If we were connecting, it's time to send a non blocking PING, we want to + * make sure the master is able to reply before going into the actual + * replication process where we have long timeouts in the order of + * seconds (in the meantime the slave would block). */ + if (server.repl_state == REDIS_REPL_CONNECTING) { + redisLog(REDIS_NOTICE,"Non blocking connect for SYNC fired the event."); + /* Delete the writable event so that the readable event remains + * registered and we can wait for the PONG reply. */ + aeDeleteFileEvent(server.el,fd,AE_WRITABLE); + server.repl_state = REDIS_REPL_RECEIVE_PONG; + /* Send the PING, don't check for errors at all, we have the timeout + * that will take care about this. */ + syncWrite(fd,"PING\r\n",6,100); + return; + } + + /* Receive the PONG command. */ + if (server.repl_state == REDIS_REPL_RECEIVE_PONG) { + char buf[1024]; + + /* Delete the readable event, we no longer need it now that there is + * the PING reply to read. */ + aeDeleteFileEvent(server.el,fd,AE_READABLE); + + /* Read the reply with explicit timeout. */ + buf[0] = '\0'; + if (syncReadLine(fd,buf,sizeof(buf), + server.repl_syncio_timeout*1000) == -1) + { + redisLog(REDIS_WARNING, + "I/O error reading PING reply from master: %s", strerror(errno)); goto error; } - /* Read the AUTH result. */ - if (syncReadLine(fd,buf,1024,server.repl_syncio_timeout) == -1) { - redisLog(REDIS_WARNING,"I/O error reading auth result from MASTER: %s", - strerror(errno)); + + /* We don't care about the reply, it can be +PONG or an error since + * the server requires AUTH. As long as it replies correctly, it's + * fine from our point of view. */ + if (buf[0] != '-' && buf[0] != '+') { + redisLog(REDIS_WARNING,"Unexpected reply to PING from master."); goto error; + } else { + redisLog(REDIS_NOTICE, + "Master replied to PING, replication can continue..."); } - if (buf[0] != '+') { - redisLog(REDIS_WARNING,"Cannot AUTH to MASTER, is the masterauth password correct?"); + } + + /* AUTH with the master if required. */ + if(server.masterauth) { + err = sendSynchronousCommand(fd,"AUTH",server.masterauth,NULL); + if (err) { + redisLog(REDIS_WARNING,"Unable to AUTH to MASTER: %s",err); + sdsfree(err); goto error; } } + /* Set the slave port, so that Master's INFO command can list the + * slave listening port correctly. */ + { + sds port = sdsfromlonglong(server.port); + err = sendSynchronousCommand(fd,"REPLCONF","listening-port",port, + NULL); + sdsfree(port); + /* Ignore the error if any, not all the Redis versions support + * REPLCONF listening-port. */ + if (err) { + redisLog(REDIS_NOTICE,"(non critical): Master does not understand REPLCONF listening-port: %s", err); + sdsfree(err); + } + } + /* Issue the SYNC command */ - if (syncWrite(fd,"SYNC \r\n",7,server.repl_syncio_timeout) == -1) { + if (syncWrite(fd,"SYNC\r\n",6,server.repl_syncio_timeout*1000) == -1) { redisLog(REDIS_WARNING,"I/O error writing to MASTER: %s", strerror(errno)); goto error; @@ -415,7 +622,7 @@ void syncWithMaster(aeEventLoop *el, int fd, void *privdata, int mask) { /* Prepare a suitable temp file for bulk transfer */ while(maxtries--) { snprintf(tmpfile,256, - "temp-%d.%ld.rdb",(int)time(NULL),(long int)getpid()); + "temp-%d.%ld.rdb",(int)server.unixtime,(long int)getpid()); dfd = open(tmpfile,O_CREAT|O_WRONLY|O_EXCL,0644); if (dfd != -1) break; sleep(1); @@ -433,16 +640,19 @@ void syncWithMaster(aeEventLoop *el, int fd, void *privdata, int mask) { goto error; } - server.replstate = REDIS_REPL_TRANSFER; - server.repl_transfer_left = -1; + server.repl_state = REDIS_REPL_TRANSFER; + server.repl_transfer_size = -1; + server.repl_transfer_read = 0; + server.repl_transfer_last_fsync_off = 0; server.repl_transfer_fd = dfd; - server.repl_transfer_lastio = time(NULL); + server.repl_transfer_lastio = server.unixtime; server.repl_transfer_tmpfile = zstrdup(tmpfile); return; error: - server.replstate = REDIS_REPL_CONNECT; close(fd); + server.repl_transfer_s = -1; + server.repl_state = REDIS_REPL_CONNECT; return; } @@ -464,11 +674,25 @@ int connectWithMaster(void) { return REDIS_ERR; } + server.repl_transfer_lastio = server.unixtime; server.repl_transfer_s = fd; - server.replstate = REDIS_REPL_CONNECTING; + server.repl_state = REDIS_REPL_CONNECTING; return REDIS_OK; } +/* This function can be called when a non blocking connection is currently + * in progress to undo it. */ +void undoConnectWithMaster(void) { + int fd = server.repl_transfer_s; + + redisAssert(server.repl_state == REDIS_REPL_CONNECTING || + server.repl_state == REDIS_REPL_RECEIVE_PONG); + aeDeleteFileEvent(server.el,fd,AE_READABLE|AE_WRITABLE); + close(fd); + server.repl_transfer_s = -1; + server.repl_state = REDIS_REPL_CONNECT; +} + void slaveofCommand(redisClient *c) { if (!strcasecmp(c->argv[1]->ptr,"no") && !strcasecmp(c->argv[2]->ptr,"one")) { @@ -476,19 +700,37 @@ void slaveofCommand(redisClient *c) { sdsfree(server.masterhost); server.masterhost = NULL; if (server.master) freeClient(server.master); - if (server.replstate == REDIS_REPL_TRANSFER) + if (server.repl_state == REDIS_REPL_TRANSFER) replicationAbortSyncTransfer(); - server.replstate = REDIS_REPL_NONE; + else if (server.repl_state == REDIS_REPL_CONNECTING || + server.repl_state == REDIS_REPL_RECEIVE_PONG) + undoConnectWithMaster(); + server.repl_state = REDIS_REPL_NONE; redisLog(REDIS_NOTICE,"MASTER MODE enabled (user request)"); } } else { + long port; + + if ((getLongFromObjectOrReply(c, c->argv[2], &port, NULL) != REDIS_OK)) + return; + + /* Check if we are already attached to the specified slave */ + if (server.masterhost && !strcasecmp(server.masterhost,c->argv[1]->ptr) + && server.masterport == port) { + redisLog(REDIS_NOTICE,"SLAVE OF would result into synchronization with the master we are already connected with. No operation performed."); + addReplySds(c,sdsnew("+OK Already connected to specified master\r\n")); + return; + } + /* There was no previous master or the user specified a different one, + * we can continue. */ sdsfree(server.masterhost); server.masterhost = sdsdup(c->argv[1]->ptr); - server.masterport = atoi(c->argv[2]->ptr); + server.masterport = port; if (server.master) freeClient(server.master); - if (server.replstate == REDIS_REPL_TRANSFER) + disconnectSlaves(); /* Force our slaves to resync with us as well. */ + if (server.repl_state == REDIS_REPL_TRANSFER) replicationAbortSyncTransfer(); - server.replstate = REDIS_REPL_CONNECT; + server.repl_state = REDIS_REPL_CONNECT; redisLog(REDIS_NOTICE,"SLAVE OF %s:%d enabled (user request)", server.masterhost, server.masterport); } @@ -497,28 +739,35 @@ void slaveofCommand(redisClient *c) { /* --------------------------- REPLICATION CRON ---------------------------- */ -#define REDIS_REPL_TIMEOUT 60 -#define REDIS_REPL_PING_SLAVE_PERIOD 10 - void replicationCron(void) { + /* Non blocking connection timeout? */ + if (server.masterhost && + (server.repl_state == REDIS_REPL_CONNECTING || + server.repl_state == REDIS_REPL_RECEIVE_PONG) && + (time(NULL)-server.repl_transfer_lastio) > server.repl_timeout) + { + redisLog(REDIS_WARNING,"Timeout connecting to the MASTER..."); + undoConnectWithMaster(); + } + /* Bulk transfer I/O timeout? */ - if (server.masterhost && server.replstate == REDIS_REPL_TRANSFER && - (time(NULL)-server.repl_transfer_lastio) > REDIS_REPL_TIMEOUT) + if (server.masterhost && server.repl_state == REDIS_REPL_TRANSFER && + (time(NULL)-server.repl_transfer_lastio) > server.repl_timeout) { - redisLog(REDIS_WARNING,"Timeout receiving bulk data from MASTER..."); + redisLog(REDIS_WARNING,"Timeout receiving bulk data from MASTER... If the problem persists try to set the 'repl-timeout' parameter in redis.conf to a larger value."); replicationAbortSyncTransfer(); } /* Timed out master when we are an already connected slave? */ - if (server.masterhost && server.replstate == REDIS_REPL_CONNECTED && - (time(NULL)-server.master->lastinteraction) > REDIS_REPL_TIMEOUT) + if (server.masterhost && server.repl_state == REDIS_REPL_CONNECTED && + (time(NULL)-server.master->lastinteraction) > server.repl_timeout) { redisLog(REDIS_WARNING,"MASTER time out: no data nor PING received..."); freeClient(server.master); } /* Check if we should connect to a MASTER */ - if (server.replstate == REDIS_REPL_CONNECT) { + if (server.repl_state == REDIS_REPL_CONNECT) { redisLog(REDIS_NOTICE,"Connecting to MASTER..."); if (connectWithMaster() == REDIS_OK) { redisLog(REDIS_NOTICE,"MASTER <-> SLAVE sync started"); @@ -529,7 +778,7 @@ void replicationCron(void) { * So slaves can implement an explicit timeout to masters, and will * be able to detect a link disconnection even if the TCP connection * will not actually go down. */ - if (!(server.cronloops % (REDIS_REPL_PING_SLAVE_PERIOD*10))) { + if (!(server.cronloops % (server.repl_ping_slave_period * REDIS_HZ))) { listIter li; listNode *ln; @@ -542,7 +791,7 @@ void replicationCron(void) { if (slave->replstate == REDIS_REPL_SEND_BULK) continue; if (slave->replstate == REDIS_REPL_ONLINE) { /* If the slave is online send a normal ping */ - addReplySds(slave,sdsnew("PING\r\n")); + addReplySds(slave,sdsnew("*1\r\n$4\r\nPING\r\n")); } else { /* Otherwise we are in the pre-synchronization stage. * Just a newline will do the work of refreshing the