MongoDB主从复制小实验
操作环境描述：WIN8 64位操作系统，内装
虚拟机为CentOS 5.5 32位系统。
操作描述：跟其他关系型
数据库类似，在主库进行数据操作，将数据同步到从节点，从节点可以配置多个。在本次试验中，master节点为主节点，我们在master节点中的对数据的插入、修改、删除操作都会同步到slave1和slave2节点。
以下为实验步骤：
（1）建立数据目录，数据目录用来存放过程中的数据。
[plain]
[root@h3 dbs]# pwd
/var/lib/mongo/dbs
[root@h3 dbs]# ls
master slave1 slave2
[root@h3 dbs]#
（2）启动master节点：
[plain]
启动master
[root@h3 dbs]# mongod --dbpath /var/lib/mongo/dbs/master --port 10000 --master --rest --nojournal
Fri Aug 2 14:10:25.498 [initandlisten] MongoDB starting : pid=19491 port=10000 dbpath=/var/lib/mongo/dbs/master master=1 32-bit host=h3
Fri Aug 2 14:10:25.498 [initandlisten]
Fri Aug 2 14:10:25.498 [initandlisten] ** NOTE: This is a 32 bit MongoDB binary.
Fri Aug 2 14:10:25.498 [initandlisten] ** 32 bit builds are limited to less than 2GB of data (or less with --journal).
Fri Aug 2 14:10:25.498 [initandlisten] ** Note that journaling defaults to off for 32 bit and is currently off.
Fri Aug 2 14:10:25.499 [initandlisten] ** See http://dochub.mongodb.org/core/32bit
Fri Aug 2 14:10:25.499 [initandlisten]
Fri Aug 2 14:10:25.500 [initandlisten] db version v2.4.5
Fri Aug 2 14:10:25.500 [initandlisten] git version: a2ddc68ba7c9cee17bfe69ed840383ec3506602b
Fri Aug 2 14:10:25.500 [initandlisten] build info:
Linux bs-linux32.10gen.cc 2.6.21.7-2.fc8xen #1 SMP Fri Feb 15 12:39:36 EST 2008 i686 BOOST_LIB_VERSION=1_49
Fri Aug 2 14:10:25.500 [initandlisten] allocator: system
Fri Aug 2 14:10:25.500 [initandlisten] options: { dbpath: "/var/lib/mongo/dbs/master", master: true, nojournal: true, port: 10000, rest: true }
Fri Aug 2 14:10:25.540 [FileAllocator] allocating new datafile /var/lib/mongo/dbs/master/local.ns, filling with zeroes...
Fri Aug 2 14:10:25.542 [FileAllocator] creating directory /var/lib/mongo/dbs/master/_tmp
Fri Aug 2 14:10:26.094 [FileAllocator] done allocating datafile /var/lib/mongo/dbs/master/local.ns, size: 16MB, took 0.545 secs
Fri Aug 2 14:10:26.094 [FileAllocator] allocating new datafile /var/lib/mongo/dbs/master/local.0, filling with zeroes...
Fri Aug 2 14:10:26.763 [FileAllocator] done allocating datafile /var/lib/mongo/dbs/master/local.0, size: 16MB, took 0.667 secs
Fri Aug 2 14:10:26.785 [initandlisten] command local.$cmd command: { create: "startup_log", size: 10485760, capped: true } ntoreturn:1 keyUpdates:0 reslen:37 12 45ms
Fri Aug 2 14:10:26.796 [initandlisten] ******
Fri Aug 2 14:10:26.796 [initandlisten] creating replication oplog of size: 50MB...
Fri Aug 2 14:10:26.799 [FileAllocator] allocating new datafile /var/lib/mongo/dbs/master/local.1, filling with zeroes...
Fri Aug 2 14:10:30.116 [FileAllocator] done allocating datafile /var/lib/mongo/dbs/master/local.1, size: 64MB, took 3.314 secs
Fri Aug 2 14:10:30.243 [initandlisten] ******
Fri Aug 2 14:10:30.245 [initandlisten] waiting for connections on port 10000
Fri Aug 2 14:10:30.247 [websvr] admin web console waiting for connections on port 11000
Fri Aug 2 14:16:52.604 [initandlisten] connection accepted from 127.0.0.1:33749 #1 (1 connection now open)
Fri Aug 2 14:16:53.885 [slaveTracking] build index local.slaves { _id: 1 }
Fri Aug 2 14:16:53.894 [slaveTrackin