[H-GEN] ssh login

[Greg Black]

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On 2003-09-25, Jason Parker-Burlingham wrote:
> Greg Black <gjb at gbch.net> writes:
> > On 2003-09-25, Sandra Milne wrote:
> >
> >> I've had an 'issue' with my debian b0x since I did a complete reinstall 
> >> about a month ago. When I connect using ssh, the prompt for a login name 
> >> appears immediately,
> 
> I'm guessing, but some SSH clients (which one are you using?) collect
> the username when the program starts up.  PuTTY does this, for
> example.

Ah, I wondered about this when I wrote my original answer; the
mention of Debian and the fact that this is a Unix users' group
had me thinking about Unix clients, not Windows stuff.

> >> but it can be anywhere from 15 up to 30 seconds before the prompt
> >> for a password appears.
> 
> In any event, this is probably the SSH client trying various methods
> to authenticate you to the remote host, eventually failing, and trying
> asking you for a password as a last resort.

Wow, are there implementations that are that slow?  I just
tested some ssh clients against a host where they have to go
through all that and then ask for a password and my clients all
take around 1 second to do the initial chatting while they go
through the various options and finally pop up a password
request.  That's why I thought 30 seconds was too much for that.

> Try using one or two -v options to your client to increase the
> verbosity of what it's doing to find out; you'll probably find it's
> trying to use RSA authentication first.

This is good advice anyway; I had intended to mention it and
somehow left it out.

> > Most weird slow stuff in ssh logins stems from incorrect setup
> > of DNS, as ssh likes to look things up.  Have you checked this?
> 
> I'd expect DNS misconfiguration to create delays longer than 15 or 30
> seconds; more like 90.

Well, I've seen delays from around 20 seconds to a couple of
minutes for DNS-related problems with ssh, although I'd agree
that something around 90 seconds is probably more common.

Perhaps Sandra will work it out and let us know.

Cheers, Greg

-- 
Greg Black <gjb at gbch.net> <http://www.gbch.net/gjb.html>
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