MongoDB进行热备份
Mongodb自带了mongodump和mongorestore这两个工具来实现对数据的备份和恢复。
mongodump能够在Mongodb运行时进行备份，它的工作原理是对运行的Mongodb做查询，然后将所有查到的文档写入磁盘。但是存在的问题时使用mongodump产生的备份不一定是数据库的实时快照，如果我们在备份时对数据库进行了写入操作，则备份出来的文件可能不完全和Mongodb实时数据相等。
mongodump 进行热备份
mongodump工具使用说明：
$ mongodump --help
Export MongoDB data to BSON files.
options:
--help produce help message
-v [ --verbose ] be more verbose (include multiple times for more
verbosity e.g. -vvvvv)
--version print the program's version and exit
-h [ --host ] arg mongo host to connect to ( <set name>/s1,s2 for
sets)
--port arg server port. Can also use --host hostname:port
--ipv6 enable IPv6 support (disabled by default)
-u [ --username ] arg username
-p [ --password ] arg password
--dbpath arg directly access mongod database files in the given
path, instead of connecting to a mongod server -
needs to lock the data directory, so cannot be used
if a mongod is currently accessing the same path
--directoryperdb if dbpath specified, each db is in a separate
directory
--journal enable journaling
-d [ --db ] arg database to use
-c [ --collection ] arg collection to use (some commands)
-o [ --out ] arg (=dump) output directory or "-" for stdout
-q [ --query ] arg json query
--oplog Use oplog for point-in-time snapshotting
--repair try to recover a crashed database
--forceTableScan force a table scan (do not use $snapshot)
参数说明：
- -h:指明数据库宿主机的IP
- -u:指明数据库的用户名
- -p:指明数据库的密码
- -d:指明数据库的名字
- -c:指明collection的名字(不指定，则所有的集合)
- -o:指明到要导出的文件名
- -q:指明导出数据的过滤条件
- -u:用户名
- -p:密码
例如：
$ mongodump -h 127.0.0.1:27021 -u 用户名 -p 密码 -d 数据库名 -o 备份文件夹名或者路径
实例：
$ mongodump -h 127.0.0.1:27021 -u xx -p xx -d kk -o bak
2018-12-20T09:58:51.473+0800 writing kk.xxxx to
2018-12-20T09:58:51.473+0800 writing kk.x2 to
2018-12-20T09:58:51.473+0800 writing kk.x3 to
2018-12-20T09:58:51.548+0800 done dumping kk.xxxx (1 document)
2018-12-20T09:58:51.550+0800 done dumping kk.x2 (29 documents)
2018-12-20T09:58:51.550+0800 done dumping kk.x3 (34 documents)
mongorestore 进行恢复数据
mongorestore 使用说明。
mongorestore --help
usage: ./bin/mongorestore [options] [directory or filename to restore from]
options:
--help produce help message
-v [ --verbose ] be more verbose (include multiple times for more
verbosity e.g. -vvvvv)
--version print the program's version and exit
-h [ --host ] arg mongo host to connect to ( <set name>/s1,s2 for sets)
--port arg server port. Can also use --host hostname:port
--ipv6 enable IPv6 support (disabled by default)
-u [ --username ] arg username
-p [ --password ] arg password
--dbpath arg directly access mongod database files in the given
path, instead of connecting to a mongod server -
needs to lock the data directory, so cannot be used
if a mongod is currently accessing the same path
--directoryperdb if dbpath specified, each db is in a separate
directory
--journal enable journaling
-d [ --db ] arg database to use
-c [ --collection ] arg collection to use (some commands)
--objcheck validate object before inserting
--filter arg filter to apply before inserting
--drop drop each collection before import
--oplogReplay replay oplog for point-in-time restore
--keepIndexVersion don't upgrade indexes to newest version
参数说明：
- -h:指明数据库宿主机的IP
- -u:指明数据库的用户名
- -p:指明数据库的密码
- -d:指明数据库的名字
- -c:指明collection的名字
- -o:指明到要备份的文件名
- -q:指明备份数据的过滤条件
- -u:用户名
- -p:密码
例如：
mongodump -h 127.0.0.1:27021 -u xx -p xxx -d kk -o path/to/bakdir
# mongorestore -h 服务器ip:27021 -u 用户名 -p 密码 -d 数据库名 --drop 备份文件目录(要定位到数据名字对应的目录)
实例：
mongorestore -h 127.0.0.1:27021 -u admin -p aicoder_com -d kk --drop ./20181220.bak/kk
2018-12-20T09:49:13.501+0800 the --db and --collection args should only be used when restoring from a BSON file. Other uses are deprecated and will not exist in the future; use --nsInclude instead
2018-12-20T09:49:13.502+0800 building a list of collections to restore from 20181220.bak/kk dir
2018-12-20T09:49:13.522+0800 reading metadata for kk.ss from 20181220.bak/kk/ss.metadata.json
2018-12-20T09:49:13.543+0800 reading metadata for kk.users from 20181220.bak/kk/users.metadata.json
2018-12-20T09:49:13.641+0800 restoring kk.ss from 20181220.bak/kk/ss.bson
2018-12-20T09:49:13.643+0800 reading metadata for kk.busers from 20181220.bak/kk/busers.metadata.json
2018-12-20T09:49:13.713+0800 restoring kk.users from 20181220.bak/kk/users.bson
2018-12-20T09:49:13.778+0800 restoring kk.busers from 20181220.bak/kk/busers.bson
2018-12-20T09:49:13.782+0800 no indexes to restore
2018-12-20T09:49:13.782+0800 finished restoring kk.users (34 documents)
2018-12-20T09:49:13.788+0800 no indexes to restore
2018-12-20T09:49:13.788+0800 finished restoring kk.ss (29 documents)
2018-12-20T09:49:13.804+0800 no indexes to restore
2018-12-20T09:49:13.804+0800 finished restoring kk.busers (1 document)
2018-12-20T09:49:13.804+0800 done
