How to get physical number of CPU sockets on Linux server

On a Linux server, you can check how many physical CPU sockets it has without opening the machine. The command is dmidecode. Installing dmidecode on CentOS:

[root@Ezylinux ~]# yum install dmidecode

To check the number of CPU sockets, run:

[root@Ezylinux ~]# dmidecode -t4 | grep Socket.Designation: | wc -l

Another method is to inspect /proc/cpuinfo by running:

[root@Ezylinux ~]# grep physical.id /proc/cpuinfo | sort -u | wc -l