Sshd Configuration

Internal

• ssh

Change the Default Port

Uncomment and/or update the default "Port" value in /etc/ssh/sshd_config:

#Port 22
Port 12345

Change the Default Port on a SELinux System

If SELinux is enable, you have to tell SELinux about the port change:

semanage port -a -t ssh_port_t -p tcp 12345

Also see How to install SELinux semanage.

Update the Firewall Rules

If iptables is enabled, there's a firewall rule that allows ssh access, and it usually mentions the port. You may want to check and change that: Iptables_Command_Line_Tool_Examples#Allow_SSH_Only_From_the_Internal_Network_on_a_Non-Standard_Port

DNS

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UseDNS no
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