How to fix "SSH is responding very slowly" ?

When we try to connect to other nodes in the cluster, SSH is responding very slowly. this is usually a dns issue, so we turn it off. For more information, please refer to: https://www.serverpronto.com/accounts/knowledgebase.php?action=displayarticle&id=16 

Solution

To test this issue, use:

1 2 arp -a # To check a lookup arp -an # To check for a reverse look up

To solve the issue, either update /etc/resolv.conf with the proper nameserver ip addresses or follow the steps below.

Update the ssh config:

1 sudo /etc/ssh/sshd_config

Find #useDNS yes

Replace with useDNS no

Restart the sshd service:

1 service sshd restart