Linux : Port Numbers for common services

 Below are some of the default port numbers in Linux

  1. SSH (Secure Shell) - port 22
  2. FTP (File Transfer Protocol) - port 20 (data) and port 21 (control)
  3. HTTP (Hypertext Transfer Protocol) - port 80
  4. HTTPS (HTTP over SSL/TLS) - port 443
  5. DNS (Domain Name System) - port 53
  6. SMTP (Simple Mail Transfer Protocol) - port 25
  7. POP3 (Post Office Protocol version 3) - port 110
  8. IMAP (Internet Message Access Protocol) - port 143
  9. NFS (Network File System) - port 2049
  10. Samba (Windows file sharing) - port 137-139 and 445

Note that these are the default port numbers for these services, but they can be configured to use different ports if needed. Also, some services may use multiple ports depending on their configuration.

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