rsync
一、rsync概述
rsync是linux系统下的数据镜像备份工具，使用快速增量备份工具remote sync可以远程同步，可以在不同主机之间进行同步，可以实现全量备份与增量备份，保持链接和权限，且采用优化的同步算法，传输前执行压缩，因此非常适合用于架构集中式的备份或异地备份等应用。同时rsync支持本地复制，或者与其他ssh、rsync主机同步。
二、rsync特性和优点
1）可以镜像保存整个目录树和文件系统
2）可以很容易做到保持原来文件的权限、时间、软硬链接等等。
3）无须特殊权限即可安装
4）快速：第一次同步时rsync复制全部内容，但在下一次值传输修改过的内容
5）压缩传输：rysnc在传输的过程中可以实行压缩及解压缩操作，可以使用更少的带宽
6）安全：可以使用scp、ssh等方式来进行文件传输
7）支持匿名传输，以方便进行网站镜像
8）选择性保持：符号链接、硬链接、文件属性、权限、时间等
三、rsync原理
1、运行模式和端口
1）采用C/S模式（实际上是一个点到点的传输，直接使用rsync命令即可完成）
2）rsync监听的端口是：873
2、四个名字的解释
1）发起端：负责发起rsync同步操作的客户端叫做发起端。通知服务器我要备份你的数据
2）备份源：负责响应来自客户端rsync同步操作的服务器叫做备份源，需要备份的服务器
3）服务端：运行rsyncd服务，一般来说，需要备份的服务器
4）客户端：存放备份数据。
3、数据同步方式
1）推push：一台主机负责吧数据传送给其他主机，服务器开销很大，比较适合后端服务器少的情况
2）拉pull：所有主机定时去找一台主机拉数据，可能就会导致数据缓慢
推：目的主机配置为rsync服务器，源主机周期性的使用rysnc命令把要同步的目录推过去（需要备份的机器是客户端，存储备份的机器是服务端）
拉：源主机配置为rysnc服务器，目的主机周期性的使用rync命令把要同步的目录拉过来（需要备份的机器是服务端，存储备份的机器是客户端）
4、rsync常用命令
//rsync命令：
rsync —a fast,versatile(通用的),remote(and local)file-copying tool
//常用选项：
-n:测试是否能执行成功
-v:显示详细的过程
-a:归档
-z:在传输的过程中压缩
-r:递归复制
-P:保持原有属性
-p:perm，保持原有权限
-e:ssh,表示使用ssh的加密功能
-q:quit，静默模式
-g:保留原文件的属组
-o:保留原文件的属主
-l:保留原文件的连接文件
四、本地及远程rsync同步
//安装rsync
[root@RS1 ~]# yum -y install rsync
//关闭防火墙和SElinux
[root@RS1 ~]# systemctl stop firewalld
[root@RS1 ~]# setenforce 0
[root@RS2 ~]# systemctl stop firewalld
[root@RS2 ~]# setenforce 0
开始本地同步
//同步本地文件
[root@RS1 ~]# ls
anaconda-ks.cfg
[root@RS1 ~]# rsync -avz anaconda-ks.cfg /opt/abc
sending incremental file list
anaconda-ks.cfg
sent 766 bytes received 35 bytes 1,602.00 bytes/sec
total size is 1,185 speedup is 1.48
[root@RS1 ~]# ll anaconda-ks.cfg /opt/abc
-rw-------. 1 root root 1185 Feb 26 02:10 anaconda-ks.cfg
-rw------- 1 root root 1185 Feb 26 02:10 /opt/abc
#其实就和cp一样，和cp没有任何区别
//同步本地目录
[root@RS1 ~]# cp dead.letter haha/
[root@RS1 ~]# tree haha/
haha/
└── dead.letter
0 directories, 1 file
[root@RS1 ~]# cd haha/
[root@RS1 haha]# mkdir ABC
[root@RS1 haha]# echo 'aabb' > ABC/index
[root@RS1 haha]# cd
[root@RS1 ~]# tree haha/
haha/
├── ABC
│ └── index
└── dead.letter
1 directory, 2 files
[root@RS1 ~]# rsync -avz haha /opt/666
sending incremental file list
created directory /opt/666
haha/
haha/dead.letter
haha/ABC/
haha/ABC/index
sent 421 bytes received 101 bytes 1,044.00 bytes/sec
total size is 223 speedup is 0.43
[root@RS1 ~]# ls /opt/
666 abc containerd data dir1 dir2
//同步多个源
[root@RS1 ~]# rsync -avz anaconda-ks.cfg haha /opt/aabb
sending incremental file list
created directory /opt/aabb
anaconda-ks.cfg
haha/
haha/dead.letter
haha/ABC/
haha/ABC/index
sent 1,159 bytes received 117 bytes 2,552.00 bytes/sec
total size is 1,408 speedup is 1.10
[root@RS1 ~]# ls /opt/
666 aabb abc containerd data dir1 dir2
[root@RS1 ~]# tree /opt/aabb/
/opt/aabb/
├── anaconda-ks.cfg
└── haha
├── ABC
│ └── index
└── dead.letter
2 directories, 3 files
五、同步文件到远程主机
[root@RS1 ~]# rsync -avz anaconda-ks.cfg root@192.168.186.131:/tmp/
The authenticity of host '192.168.186.131 (192.168.186.131)' can't be established.
ECDSA key fingerprint is SHA256:+tvDQCu4JzfrZXBekLFvNB+FH7aKP7NrYKmUhF0B+lU.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '192.168.186.131' (ECDSA) to the list of known hosts.
root@192.168.186.131's password:
sending incremental file list
anaconda-ks.cfg
sent 766 bytes received 35 bytes 84.32 bytes/sec
total size is 1,185 speedup is 1.48
[root@RS2 ~]# ls /tmp/
anaconda-ks.cfg
将远程主机文件同步到本地
//做免密登录
[root@RS1 ~]# ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /root/.ssh/id_rsa.
Your public key has been saved in /root/.ssh/id_rsa.pub.
The key fingerprint is:
SHA256:Vfk1hKh6T80u+AwkbOb+BRFQTpM2ryeT7Dc7qctT/YE root@RS1
The key's randomart image is:
+---[RSA 2048]----+
| .o=. o.o. |
| o+oo.. ..|
| .o= . ..|
| . o.. . |
| =Soo + . |
| +.oB.+ E . |
| .o.O.o . .|
| . .++B . . |
| ..=*+= |
+----[SHA256]-----+
[root@RS1 ~]# ssh-copy-id root@192.168.186.131
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@192.168.186.131's password:
Number of key(s) added: 1
Now try logging into the machine, with: "ssh 'root@192.168.186.131'"
and check to make sure that only the key(s) you wanted were added.
//远程主机同步到本地（绝对路径）
[root@RS1 ~]# rsync -avz /root/haha/ root@192.168.186.131:/tmp/
sending incremental file list
./
dead.letter
ABC/
ABC/index
sent 403 bytes received 65 bytes 936.00 bytes/sec
total size is 223 speedup is 0.48
[root@RS2 ~]# tree /tmp/
/tmp/
├── ABC
│ └── index
└── dead.letter
1 directory, 2 files
六、rsync+inotify
环境说明：
| 服务器类型 | IP地址 | 应用 | 操作系统 |
|---|---|---|---|
| 源服务器 | 192.168.186.130 | rsync inotify-tools 脚本 |
redhat 8 |
| 目标服务器 | 192.168.186.131 | rsync | redhat 8 |
需求：
- 把源服务器上/etc目录实时同步到目标服务器的/tmp/下
在目标服务器上做以下操作：
//安装rsync服务端软件
[root@RS2 ~]# yum -y install rsync
//设置rsyncd.conf配置文件
[root@RS2 ~]# vim /etc/rsyncd.conf
log file = /var/log/rsyncd.log
pidfile = /var/run/rsyncd.pid
lock file = /var/run/rsync.lock
secrets file = /etc/rsync.pass
[opt] path = /tmp/
comment = sync etc from client
uid = root
gid = root
port = 873
ignore errors
use chroot = no
read only = no
list = no
max connections = 200
timeout = 600
auth users = admin
//创建用户认证文件
[root@RS2 ~]# echo 'admin:123456' > /etc/rsync.pass
[root@RS2 ~]# cat /etc/rsync.pass
admin:123456
//设置文件权限
[root@RS2 ~]# chmod 600 /etc/rsync*
[root@RS2 ~]# ll /etc/rsync*
-rw------- 1 root root 410 May 11 17:28 /etc/rsyncd.conf
-rw------- 1 root root 13 May 11 17:29 /etc/rsync.pass
//启动rsync服务
[root@RS2 ~]# rsync --daemon
[root@RS2 ~]# ss -antl
State Recv-Q Send-Q Local Address:Port Peer Address:Port
LISTEN 0 128 0.0.0.0:22 0.0.0.0:*
LISTEN 0 128 0.0.0.0:9000 0.0.0.0:*
LISTEN 0 5 0.0.0.0:873 0.0.0.0:*
LISTEN 0 128 [::]:22 [::]:*
LISTEN 0 5 [::]:873 [::]:*
在源服务器上做以下操作：
//安装rsync服务端软件
[root@RS1 ~]# yum -y install rsync
//创建认证密码文件
[root@RS1 ~]# echo '123456' > /etc/mypass
[root@RS1 ~]# cat /etc/mypass
123456
//设置文件权限，只设置文件所有者具有读取、写入权限即可
[root@RS1 ~]# chmod 600 /etc/mypass
[root@RS1 ~]# ll /etc/mypass
-rw------- 1 root root 7 May 11 17:41 /etc/mypass
//在源服务器上创建测试目录，然后在源服务器运行以下命令
[root@RS1 ~]# rsync -avH --port 873 --progress --delete /root/anaconda-ks.cfg admin@192.168.186.131::opt --password-file=/etc/mypass
sending incremental file list
anaconda-ks.cfg
1,185 100% 0.00kB/s 0:00:00 (xfr#1, to-chk=0/1)
sent 1,294 bytes received 43 bytes 2,674.00 bytes/sec
total size is 1,185 speedup is 0.89
[root@RS2 ~]# ls /tmp/
anaconda-ks.cfg
//安装inotify-tools工具，实时触发rsync进行同步
[root@RS1 ~]# yum -y install inotify-tools
//查看服务器内核是否支持inotify
[root@RS1 ~]# ll /proc/sys/fs/inotify/
total 0
-rw-r--r-- 1 root root 0 May 11 17:53 max_queued_events
-rw-r--r-- 1 root root 0 May 11 17:53 max_user_instances
-rw-r--r-- 1 root root 0 May 11 17:53 max_user_watches
//如果有这三个max开头的文件则表示服务器内核支持inotify
//写同步脚本
[root@RS1 ~]# mkdir /scripts
[root@RS1 ~]# touch /scripts/inotify.sh
[root@RS1 ~]# chmod 755 /scripts/inotify.sh
[root@RS1 ~]# ll /scripts/inotify.sh
-rwxr-xr-x 1 root root 0 May 11 17:58 /scripts/inotify.sh
[root@RS1 ~]# vim /scripts/inotify.sh
#bin/bash
host=192.168.186.131
src=/opt
des=opt
password=/etc/mypass
user=admin
inotifywait=/usr/bin/inotifywait
$inotifywait -mrq --timefmt '%Y%m%d %H:%M' --format '%T %w%f%e' -e modify,delete,create,attrib $src \
| while read files;do
rsync -avzP --delete --timeout=100 --password-file=${password} $src $user@$host::$des
echo "${files} was rsynced" >>/tmp/rsync.log 2>&1
done
//启动脚本
[root@RS1 ~]# nohup /bin/bash /scripts/inotify.sh &
[1] 22546
[root@RS1 ~]# nohup: ignoring input and appending output to 'nohup.out'
[root@RS1 ~]# ps -ef|grep inotify
root 22546 2260 0 18:25 pts/0 00:00:00 /bin/bash /scripts/inotify.sh
root 22547 22546 0 18:25 pts/0 00:00:00 /usr/bin/inotifywait -mrq --timefmt %Y%m%d %H:%M --format %T %w%f%e -e modify,delete,create,attrib /opt
root 22548 22546 0 18:25 pts/0 00:00:00 /bin/bash /scripts/inotify.sh
root 22619 2260 0 18:26 pts/0 00:00:00 grep --color=auto inotify
//在源服务器上生成一个新文件
[root@RS1 opt]# touch abc
[root@RS1 ~]# echo 'ccccccccc' > /opt/abc
//查看inotify生成的日志
[root@RS1 opt]# tail /tmp/rsync.log
20210511 18:34 /opt/abcMODIFY was rsynced
//从日志上可以看到，我们生成了一个abc文件，并且添加了内容到其里面
//在目标服务器查看
[root@RS2 ~]# ll /tmp/opt/
total 8
-rw-r--r-- 1 root root 13 May 11 18:34 abc
[root@RS2 ~]# cat /tmp/opt/abc
ccccccccc
设置脚本开机自动启动：
[root@RS1 ~]# chmod +x /etc/rc.d/rc.local
[root@RS1 ~]# ll /etc/rc.d/rc.local
-rwxr-xr-x. 1 root root 474 Feb 26 2019 /etc/rc.d/rc.local
[root@RS1 ~]# echo 'nohup /bin/bash /scripts/inotify.sh' >> /etc/rc.d/rc.local
[root@RS1 ~]# tail /etc/rc.d/rc.local
#
# In contrast to previous versions due to parallel execution during boot
# this script will NOT be run after all other services.
#
# Please note that you must run 'chmod +x /etc/rc.d/rc.local' to ensure
# that this script will be executed during boot.
touch /var/lock/subsys/local
nohup /bin/bash /scripts/inotify.sh
[root@RS1 ~]# tree /opt/
/opt/
├── abc
├── cccd
├── containerd
│ ├── bin
│ └── lib
└── test
└── abc
[root@RS2 ~]# tree /tmp/opt/
/tmp/opt/
├── abc
├── cccd
├── containerd
│ ├── bin
│ └── lib
└── test
└── abc
[root@RS2 ~]# vim /usr/lib/systemd/system/rsyncd.service
[Unit]
Description=fast remote file copy program daemon
ConditionPathExists=/etc/rsyncd.conf
[Service]
EnvironmentFile=/etc/sysconfig/rsyncd
ExecStart=/usr/bin/rsync --daemon --no-detach "$OPTIONS"
[Install]
WantedBy=multi-user.target
[root@RS2 ~]# vim /usr/lib/systemd/system/rsyncd.service
[root@RS2 ~]# echo 'OPTIONS=""' > /etc/sysconfig/rsyncd
[root@RS2 ~]# systemctl enable --now rsyncd
Created symlink /etc/systemd/system/multi-user.target.wants/rsyncd.service → /usr/lib/systemd/system/rsyncd.service.
