SSH timeout after Hostname change


I have a mailserver running iRedmail - due to some issues with rDNS and ptr records, I was required to change the hostname.

I changed the following config files:

/etc/hosts /etc/hostname /etc/ssl/<redacted>

Since this change, I’ve been unable to SSH into the server - I’ve tried multiple points of entry, locally using Putty and from several remote VPSs, all fail with a connection timeout. An example of the timeout:

user@server:~$ ssh -v <user>@<FQDN> -p <port> OpenSSH_6.6.1, OpenSSL 1.0.1f 6 Jan 2014 debug1: Reading configuration data /etc/ssh/ssh_config debug1: /etc/ssh/ssh_config line 19: Applying options for * debug1: Connecting to <redacted> port <port>. debug1: connect to address <redacted> port <port> Connection timed out ssh: connect to host <redacted> port <port>: Connection timed out

Putty shows almost identical logging output.

I’ve recursively grep’d for the old hostname:

sudo grep -Rio “<old_hostname>” /

Initially, this turned up some PKI entries, so I simply piped the output into sed -i. I’ve since checked and there are no more references to the old hostname anywhere, yet I still cannot connect. Of course, I’ve rebooted the server a number of times and ensured all available services are running - if I attempt to SSH into the default port (from which I’ve changed), I immediately get connection refused.

FYI: I can login via tty1 (console access).

Any help or advice would be appreciated

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In what you posted, nothing confirms that ssh is actually running.

What does systemctl status sshd reports?

If your OS doesn’t have systemd, try ps ax | grep sshd.

Also, try running an nmap scan against your problematic droplet’s ssh port.

That was it - I had opened the required port months ago and forgot to persist the change, so the reboot after changing the hostname dropped that change.

Thanks for your help!

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