How To Disable SSH reverse DNS Lookups in Linux/Unix

Directive 'UseDNS' is not allowed within a Match block mikeshinn February 01, 2018 18:23; Updated; Follow. This occurs when sshd configuration has been modified to Nov 30, 2017 · Once at the bottem you will need to add the following, “UseDNS no” Save and Exit Vi editor; Now, restart ssh with the following command systemctl restart sshd Then check the status of SSHD with “systemctl status sshd” Once done, exit and try to reconnect to the server. See if disabling DNS solved the issue. Jan 22, 2020 · The UseDNS setting sends the hostname to the Password Authentication Module (PAM), which ships with cPanel & WHM, for SSH session authentication. cPHulk also requests authentication information from the PAM to determine whether a login attempt could be a brute force attack. Not sure if this is possible, given how UseDNS kicks into action before the user has any chance to authentify. It is probably easier to fix name resolution. If DNS is out of your control, you could add an entry to /etc/hosts, that should fix the problem. Hi All, I am using putty tool to login to Redhat linux thru SSH. We are using lot of Redhat linux server, but in one of Redhat linux servers, it is delaying long (>30secs) to get the password prompt after enter the user name in login prompt. Why there is delay between login prompt and password pr Nov 28, 2017 · The UseDNS directive controls the above functionality; to disable it, search and uncomment it in the /etc/ssh/sshd_config file. If it’s not set, add it with the value no . UseDNS no Sep 15, 2010 · Hi experts, We are getting slow ssh session connections at HP-UX 11.31 servers. We have set the parameters that maybe will affect , and commented at other theads at config file sshd_config : UseDNS no X11Forwarding yes X11DisplayOffset 10 X11UseLocalhost no GSSAPIAuthentication no. (7 Replies)

linux - SCP error: Bad configuration option

Features - Fail2ban Feb 10, 2017 Setting UseDNS in sshd_conf | cPanel Forums

UseDNS Specifies whether sshd(8) should look up the remote host name, and to check that the resolved host name for the remote IP address maps back to the very same IP address. If this option is set to no (the default) then only addresses and not host names may be used in ~/.ssh/authorized_keys from and sshd_config Match Host directives.

Yes setting UseDNS to no in the sshd_config file on the *remote* machine will cure the symptom but it will not cure the underlying problem that DNS lookups on the remote machine are not working as they should, the most likely reason being that your local machine does not have a DNS record. Mar 15, 2014 · The commands presented above can be executed using: $ fail2ban-client or by typing them in the interactive console available with: $ fail2ban-client -i UseDNS no; Note. The location of this configuration file can differ for your distribution or if you are not running OpenSSH. If this is the case, consult the relevant