You can view default firewall rules and customize rules for your GitHub Enterprise instance.

In this guide

About your GitHub Enterprise instance's firewall

GitHub Enterprise uses Ubuntu's Uncomplicated Firewall (UFW) on the virtual appliance. For more information see "UFW" in the Ubuntu documentation. GitHub Enterprise automatically updates the firewall whitelist of allowed services with each release.

After you install GitHub Enterprise, all required network ports are automatically opened to accept connections. Every non-required port is automatically configured as deny, and the default outgoing policy is configured as allow. Stateful tracking is enabled for any new connections; these are typically network packets with the SYN bit set. For more information, see "Network ports."

The UFW firewall also opens several other ports that are required for GitHub Enterprise to operate properly. For more information on the UFW ruleset, see the UFW README.

Viewing the default firewall rules

  1. SSH into your GitHub Enterprise instance.

    ssh -p 122 admin@HOSTNAME
    
  2. To view the default firewall rules, use the sudo ufw status command. You should see output similar to this:

    sudo ufw status
    Status: active
    To                         Action      From
    --                         ------      ----
    ghe-1194                   ALLOW       Anywhere
    ghe-122                    ALLOW       Anywhere
    ghe-161                    ALLOW       Anywhere
    ghe-22                     ALLOW       Anywhere
    ghe-25                     ALLOW       Anywhere
    ghe-443                    ALLOW       Anywhere
    ghe-80                     ALLOW       Anywhere
    ghe-8080                   ALLOW       Anywhere
    ghe-8443                   ALLOW       Anywhere
    ghe-9418                   ALLOW       Anywhere
    ghe-1194 (v6)              ALLOW       Anywhere (v6)
    ghe-122 (v6)               ALLOW       Anywhere (v6)
    ghe-161 (v6)               ALLOW       Anywhere (v6)
    ghe-22 (v6)                ALLOW       Anywhere (v6)
    ghe-25 (v6)                ALLOW       Anywhere (v6)
    ghe-443 (v6)               ALLOW       Anywhere (v6)
    ghe-80 (v6)                ALLOW       Anywhere (v6)
    ghe-8080 (v6)              ALLOW       Anywhere (v6)
    ghe-8443 (v6)              ALLOW       Anywhere (v6)
    ghe-9418 (v6)              ALLOW       Anywhere (v6)
    

Adding custom firewall rules

Warning: Before you add custom firewall rules, back up your current rules in case you need to reset to a known working state. If you're locked out of your server, contact GitHub Enterprise Support to reconfigure the original firewall rules. Restoring the original firewall rules involves downtime for your server.

  1. Configure a custom firewall rule.
  2. Check the status of each new rule with the status numbered command.

    sudo ufw status numbered
    
  3. To back up your custom firewall rules, use the cpcommand to move the rules to a new file.

    sudo cp -r /lib/ufw ~/ufw.backup
    

After you upgrade your GitHub Enterprise instance, you must reapply your custom firewall rules. We recommend that you create a script to reapply your firewall custom rules.

Restoring the default firewall rules

If something goes wrong after you change the firewall rules, you can reset the rules from your original backup.

Warning: If you didn't back up the original rules before making changes to the firewall, contact GitHub Enterprise Support for further assistance.

  1. SSH into your GitHub Enterprise instance.

    ssh -p 122 admin@HOSTNAME
    
  2. To restore the previous backup rules, copy them back to the firewall with the cp command.

    sudo cp -f ~/ufw.backup/*rules /lib/ufw
    
  3. Restart the firewall with the systemctl command.

    sudo systemctl restart ufw
    
  4. Confirm that the rules are back to their defaults with the ufw status command.

    sudo ufw status
    Status: active
    To                         Action      From
    --                         ------      ----
    ghe-1194                   ALLOW       Anywhere
    ghe-122                    ALLOW       Anywhere
    ghe-161                    ALLOW       Anywhere
    ghe-22                     ALLOW       Anywhere
    ghe-25                     ALLOW       Anywhere
    ghe-443                    ALLOW       Anywhere
    ghe-80                     ALLOW       Anywhere
    ghe-8080                   ALLOW       Anywhere
    ghe-8443                   ALLOW       Anywhere
    ghe-9418                   ALLOW       Anywhere
    ghe-1194 (v6)              ALLOW       Anywhere (v6)
    ghe-122 (v6)               ALLOW       Anywhere (v6)
    ghe-161 (v6)               ALLOW       Anywhere (v6)
    ghe-22 (v6)                ALLOW       Anywhere (v6)
    ghe-25 (v6)                ALLOW       Anywhere (v6)
    ghe-443 (v6)               ALLOW       Anywhere (v6)
    ghe-80 (v6)                ALLOW       Anywhere (v6)
    ghe-8080 (v6)              ALLOW       Anywhere (v6)
    ghe-8443 (v6)              ALLOW       Anywhere (v6)
    ghe-9418 (v6)              ALLOW       Anywhere (v6)