1.Background of the problem
When creating the MySQL replication link from the node, because the virtual machine is copied from a template, the server ID is the same.
2. Solutions
# edit/etc/my.cnf
vi /etc/my.cnf
# Add the following 2 lines of code
# server-id here, as long as it is not the same, my mysql master node is 1, here I set it to 2
log-bin=mysql-bin
server-id=2
#restart mysql
systemctl restart mysql