SSH takes a few minutes to login

Dj_Jestar · 21 Nov 2007 at 10:47

On one of my boxes, when I SSH to it, it takes a few mins to login. Even on LAN when I am sat next to it.

I think it's reverse host lookup, but I can't find anywhere to change the config. Any one know where I can find it? also any other suggestions to the slow down?

shine · 21 Nov 2007 at 10:51

If it is the reverse host lookup try adding your IP to the hosts file and see that fixes it.

Dj_Jestar · 21 Nov 2007 at 11:23

I'll give it a go as a test. Do you know how to switch off the reverse lookup completely?

shine · 21 Nov 2007 at 11:52

No, I've never needed to turn off reverse lookups.

Dj_Jestar · 21 Nov 2007 at 12:23

Ok, ta. The test proved it is reverse lookups at fault.

ChrisB · 21 Nov 2007 at 13:15

The generic way is to add (to /etc/sysconfig/sshd)

Code:

OPTIONS="-u0"

Should disable it all together

Dj_Jestar · 21 Nov 2007 at 14:18

lo poly

I've sorted it now; I discovered the wonderful setting of:

Code:

UseDNS no

in sshd_config

lbt · 21 Nov 2007 at 16:56

you may want to fix reverse lookup properly - other applications will bite you too.

Do you run your own DNS server? (bind/named)

Dj_Jestar · 21 Nov 2007 at 19:02

we do, and we don't. The machine is currently on our network, but will eventually be "out there" with gprs modems on the public network/isp network.

We are dependent on reverse lookups for other stuff afaik, and the only issue we've had so far is with sshd.