为了提升逼格,我决定使用英文版的的这句作为开头,尽管我最初想到的是中文版orz
天灾人祸这种事,总归是有的。尽管服务器的灾难性故障不常发生,概率也比遇到鬼或是遇到爱情来得高些,将风险考虑在内总归是好的,所谓有备无患。如果你已经在自己的架构中将单点故障考虑进去了,就不必往下拉啦,继续舔酸奶盖去吧~如果你的云服务商已经考虑了单点故障,你也没啥好做啦。
如果两者都没有,你应该请我喝杯星冰乐再往下拉。
ps:我最近多是在处理性能优化,数据迁移,安全策略,系统稳定性这类事,简直是伪装成开发的运维orz
策略
采用异地备份来应对单点故障导致的数据丢失
最初的思路
首先明确我们需要备份哪些数据,关于edX数据,可以参考我此前的这篇文章
一番深(hu)思(si)熟(luan)虑(xiang)之后,你会发现,我们关心的数据无非是数据库(mongodb/mysql)里存的,以及静态文件(/edx/var/edxapp/staticfiles)
思路很简单,每天定时备份数据库和静态文件,将其同步到远程服务器。只保存最近3,5天的备份文件,逾期的删除
这里需要注意的问题可能有三点:
- 不要影响到用户使用,备份是消耗服务器资源的,会造成服务器压力,写个定时任务,让其在凌晨做
- 采用增量同步的方式节省带宽
- 任务完成后,给自己发个邮件,确定成功执行了
那么写个shell脚本基本就完事啦,主要可能涉及的工具:
- mongodump
- mysqldump
- tar
- scp/rsync
- crontab
backup闪亮登场
就在我shell脚本快写完的时候,在github上发现了这个东西:backup
一言话概括就是
Easy full stack backup operations on UNIX-like systems
稍微扫一眼Overview,分分钟爱不释手啊。
从文档中不难发现,backup本质上是对以上我们提到的工具做了封装。
能不写shell,我是尽量不写shell的。
先读下文档吧。
install backup
backup是ruby写的,使用gem安装。不得不说ruby的DSL能力真强啊
sudo gem install backup
哦,顺便说下,我在ruby1.8.7和ruby1.9.3下都没成功,之后在ubuntu12.04上手动编译了ruby2.0.0才安装好backup。也是蛮诡异的,可能是我机器的问题,文档里说ruby1.8.7和ruby1.9.3应该都是没有问题的
backup demo
从一个简单的案例开始。
任务描述:备份我的home目录下的所有文件,同步到远程服务器的~/backup_my_home
目录,只保留最近的5个备份
在shell里执行
backup generate:model --trigger backup_my_home --archives --storages=‘scp‘ --compressor=‘gzip‘
会生成:Generated model file: ‘/home/USERNAME/Backup/models/backup_my_home.rb‘
编辑以上文件就行
# encoding: utf-8 Model.new(:backup_my_home, ‘Description for backup_my_home‘) do archive :my_archive do |archive| # Run the `tar` command using `sudo` # archive.use_sudo archive.add "/home/USERNAME" end # SCP (Secure Copy) [Storage] # store_with SCP do |server| server.username = "my_username" server.password = "my_password" server.ip = "123.45.678.90" server.port = 22 server.path = "~/backup_my_home/" server.keep = 5 end # Gzip [Compressor] compress_with Gzip end
几乎无需解释对吧:)
开始备份:backup perform -t backup_my_home
开始备份edX
静态文件
backup generate:model --trigger edx_staticfile_backup --archives --storages=‘scp‘ --compressor=‘gzip‘
# encoding: utf-8 Model.new(:edx_staticfile_backup, ‘Description for edx_staticfile_backup‘) do # archive.root ‘/path/to/archive/root‘ # archive :my_archive do |archive| # Run the `tar` command using `sudo` # archive.use_sudo #archive.add "/path/to/a/file.rb" archive.add "/edx/var/edxapp/staticfiles" #archive.exclude "/path/to/a/excluded_file.rb" #archive.exclude "/path/to/a/excluded_folder" end ## # SCP (Secure Copy) [Storage] #你需要先去目标服务器建立~/edx_backups/staticfile目录 store_with SCP do |server| server.username = "my_username" server.password = "my_password" server.ip = "123.45.678.90" server.port = 22 server.path = "~/edx_backups/staticfile" server.keep = 5 # Additional options for the SSH connection. # server.ssh_options = {} end ## # Gzip [Compressor] # compress_with Gzip end
备份mongo
databases
>mongo >show dbs admin cs_comments_service_development edxapp local
为mongo添加用户
>mongo >use edxapp >db.addUser(“wwj”, “xxx”)
backup generate:model --trigger edx_mongodb_backup --databases="mongodb" --storages=‘scp‘ --compressor=‘gzip‘ --notifiers=‘mail‘
# encoding: utf-8 Model.new(:edx_mongodb_backup, ‘Description for edx_mongodb_backup‘) do ## # MongoDB [Database] # database MongoDB do |db| db.name = "edxapp" #db.name = :all db.username = "wwj" db.password = "xxx" db.host = "localhost" db.port = 27017 db.ipv6 = false #db.only_collections = ["only", "these", "collections"] #db.additional_options = [] db.lock = false db.oplog = false end ## # SCP (Secure Copy) [Storage] # store_with SCP do |server| server.username = "my_username" server.password = "my_password" server.ip = "123.45.678.90" server.port = 22 server.path = "~/edx_backups/mongo" server.keep = 5 # Additional options for the SSH connection. # server.ssh_options = {} end ## # Gzip [Compressor] # compress_with Gzip notify_by Mail do |mail| mail.on_success = true mail.on_warning = true mail.on_failure = true mail.from = "[email protected]" mail.to = "[email protected]" mail.address = "smtp.gmail.com" mail.port = 587 mail.domain = "your.host.name" mail.user_name = "[email protected]" mail.password = "my_password" mail.authentication = "plain" mail.encryption = :starttls end end
备份mysql
databases
text >mysql -u root >show databases; +--------------------+ | Database | +--------------------+ | information_schema | | edxapp | | mysql | | ora | | performance_schema | | test | | xqueue | +--------------------+
backup generate:model --trigger edx_mysql_backup --databases="mysql" --storages=‘scp‘ --compressor=‘gzip‘
# encoding: utf-8 Model.new(:edx_mysql_backup, ‘Description for edx_mysql_backup‘) do ## # MySQL [Database] # database MySQL do |db| # To dump all databases, set `db.name = :all` (or leave blank) #db.name = "my_database_name" db.name = "edxapp" db.username = "root" db.password = "" db.host = "localhost" db.port = 3306 #mysql.sock 位置有变 #db.socket = "/tmp/mysql.sock" # Note: when using `skip_tables` with the `db.name = :all` option, # table names should be prefixed with a database name. # e.g. ["db_name.table_to_skip", ...] #db.skip_tables = ["skip", "these", "tables"] #db.only_tables = ["only", "these", "tables"] db.additional_options = ["--quick", "--single-transaction"] end ## # SCP (Secure Copy) [Storage] # store_with SCP do |server| server.username = "my_username" server.password = "my_password" server.ip = "123.45.678.90" server.port = 22 server.path = "~/edx_backups/mysql" server.keep = 5 # Additional options for the SSH connection. # server.ssh_options = {} end ## # Gzip [Compressor] # compress_with Gzip end
开始备份
backup perform -t edx_staticfile_backup backup perform -t edx_mongodb_backup backup perform -t edx_mysql_backup
定时任务
每天凌晨3:00
sudo crontab -e
写入
00 03 * * * /usr/local/bin/backup perform -t edx_staticfile_backup 00 03 * * * /usr/local/bin/backup perform -t edx_mongodb_backup 00 03 * * * /usr/local/bin/backup perform -t edx_mysql_backup
后续
之后我们还是采用rsync的做法吧,不然数据大到一定程度,太浪费带宽了
只要更改store_with就行
注意:数据服务器到备份服务器应当配置好ssh免登陆
compress_with Gzip do |gzip| gzip.rsyncable = true end store_with RSync do |storage| time = Time.now storage.mode = :ssh storage.host = "123.45.67.89" storage.port = 22 storage.ssh_user = "wwj" #免密码ssh #每周为一轮,使用的是同名覆盖 path = time.strftime ‘%A‘ storage.path = "~/edx_backups/staticfile/#{ path }" end
注意
~/Backup/log/backup.log 中的时间是ruby的时间,与本地差(晚)8个小时。时区的问题