We can connect to the mysqld server by using Unix Socket file or by using TCP/IP. A connection using Unix socket file is faster than TCP/IP but socket file used when connecting to a server on the same computer. Hostname and port can be skip when we use a Unix socket file.
Locate a Unix Soket File:
[ec2-user@ip-172-xx-xx-x ~]$ mysql -u root -p -h 127.0.0.1 -e "select @@socket"
Enter password:
+---------------------------+
| @@socket |
+---------------------------+
| /var/lib/mysql/mysql.sock |
Or
[ec2-user@ip-172-xx-xx-x ~]$ cat /etc/my.cnf|grep socket
socket=/var/lib/mysql/mysql.sock
Check Connection using Unix Socket File:
[ec2-user@ip-172-xx-xx-x ~]$ mysql -u root -p -S /var/lib/mysql/mysql.sock
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 13
Server version: 8.0.34 MySQL Community Server - GPL
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