install

Server side

Install software:

yum  -y  install  rsync

To create a directory to synchronize:

mkdir  -p  /data

Edit the configuration file: vim /etc/rsyncd.conf

motd file = /etc/rsyncd.motd
transfer logging = yes
log file = /var/log/rsyncd.log #Log storage path
port = 873  #Port number
address = 192.168.0.37  #IP address
uid = root #User name used
gid = root  #Password used
use chroot = no
read only = no
max connections = 10
[common]
comment = rsync lee
path = /data
ignore errors
auth users = simops
secrets file = /etc/rsyncd.secrets
hosts allow = 192.168.0.0/255.255.255.0 #Allowed address segments
hosts deny = *
list = false

UID = 0
GID = 0

Create user password:

echo  "simops:123456"  >  /etc/rsyncd.secrets
chmod  600  /etc/rsyncd.secrets

To create a prompt file:

echo  "rsync simops"  >  /etc/rsyncd.motd

To configure firewall rules and turn off SElinux:

iptables  -I  INPUT  -p  tcp  --dport  873  -j  ACCEPT
setenforce 0 #Temporarily shut down SElinux

Start service:

rsync  --daemon
echo  "rsync  --daemon"  >>  /etc/rc.local

II. Client (192.168.0.17):

Install software:

yum  -y  install  rsync

To create a directory to synchronize:

mkdir  -p  /data

Create password file (password free):

echo  "123456"  >  /root/passwd
chmod  600  /root/passwd

Pull:

rsync  -avz  --password-file=/root/passwd  simops@192.168.0.37::common  /data/

Push

rsync  -avz  --password-file=/root/passwd  /data  simops@192.168.0.37::common

Encounter problems

1. Error is reported after the push command is executed

rsync  -avz  --password-file=/root/passwd  lee@192.168.0.37::common  /home/lee/rsync/
rsync  lee

@ERROR: invalid uid root #User name used
rsync error: error starting client-server protocol (code 5) at main.c(1648) [Receiver=3.1.2]

Solution add the following two lines to the rsyncd.conf file to solve the problem

UID = 0 
GID = 0 

2. The server has no permission to synchronize the directory

rsync  -avz  --password-file=/root/passwd  simops@192.168.0.37::common  /home/lee/rsync/
rsync  lee

@ERROR: chdir failed
rsync error: error starting client-server protocol (code 5) at main.c(1648) [Receiver=3.1.2]

Solution: the server-side synchronization directory does not have permission. The default user of cwrsync is Svcwrsync. Add user Svcwrsync permission for synchronization directory

3. selinux is not closed

rsync  -avz  --password-file=/root/passwd simops@192.168.0.37::common  /data/
rsync  lee

receiving incremental file list
rsync: opendir "." (in common) failed: Permission denied (13)

sent 20 bytes  received 108 bytes  256.00 bytes/sec
total size is 0  speedup is 0.00
rsync error: some files/attrs were not transferred (see previous errors) (code 23) at main.c(1650) [generator=3.1.2]

This problem seems to have been synced, but it was not synced when I went to check it
Check the selinux problem in detail, and close it