Re: SSH slowness
On 01/20/2008 04:29 PM, Curt Howland wrote:
In the last few days, ssh connections have turned dog slow. I mean
very slow, like 20-30 seconds of just sitting there after
issuing "ssh server" before it asks for my password.
This is very strange, as both client and server are on the same LAN
with an average ping response time of 1.1ms.
Does ssh do a dns lookup or something that could be messing up?
Yes. The SSH server performs a reverse DNS lookup on the connecting IP
address. If there is no reverse DNS record for that IP address or the
name server is foobar'ed, the SSH server will wait until timeout on the
DNS lookup, then prompt for password and log the connection by IP.
Sounds like something on the LAN changed a few days ago - someone jacked
up the in-addr.arpa zone for that range, the name server itself is not
functioning properly.. you can get around it temporarily by adding
IP/host entries to /etc/hosts file on the server you are connecting to.
--
Kind Regards,
Michael Shuler
Reply to: