ssh into vm takes a long time but eventually logs me in

asked 2017-12-13 15:16:00 -0500

jcorkey gravatar image

I can't figure out why it is taking a long time to ssh into any vm I create on openstack. Once I am finally logged into the vm, things seem to be running just fine and not slow. But When I try to ssh into the vm it takes about 45 seconds to a minute to prompt me for a password to log in. After I type in my password it logs right in with no delay.

I used kolla 5.0.0 to deploy openstack on one control node and one compute node both running Centos 7. Everything seems to work well but the ssh login just takes too long.

Any suggestions on why this could be happening?

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It could be the option UseDNS in /etc/ssh/sshd_config on the VM. By default, it's YES, so that the sshd tries to look up the client using DNS. The 45-60 seconds you experience are the time it takes to give up the DNS lookup.

Bernd Bausch gravatar imageBernd Bausch ( 2017-12-13 17:04:35 -0500 )edit

I tried changing that. It logs in about 10 seconds faster but still slow which is strange. Also, I have another all-in-one setup with instances that I can ssh into with no delay but on this new setup, I get a delay ssh into instances on this multinode setup I deployed with kolla 5.0.0.

jcorkey gravatar imagejcorkey ( 2017-12-14 09:37:05 -0500 )edit