sshd starts slooooowly

Tinkster · 04-13-2003, 02:56 PM

Hi Guys,

I've asked this question on LQ before, but
couldn't find a satisfactory answer.

Why could sshd possibly take 30 seconds to start
up on a PIV 1.8GHZ?

I subscribed to the ssh list and asked the quesstion
there, however, the mod felt it doesn't fit his list, bounced
my mail and told me to go ask in a Slackware-specific
forum ... :/

I find it annoying to wait for 30 seconds for something
that used to take like 2 seconds on my old machine
(a PII 266) ...

Cheers,
Tink

david_ross · 04-13-2003, 03:24 PM

Does it stop and start OK after boot?

You could try stopping it then starting it in debug mode:
sshd -ddde

The e forces it to print the data to the console rather than the message log. This should let you see at what point it is slow.

Tinkster · 04-13-2003, 05:15 PM

/me is puzzled, scratches his head ...

Well, takes about a split second that way,
no error messages whatsoever....

Cheers,
Tink

david_ross · 04-13-2003, 05:18 PM

That does seem odd.

Maybe there is something about the first time it is run. What about stopping it from running on boot then starting it manually afterwards with the debug command?

unSpawn · 04-13-2003, 05:26 PM

How about stracing it: "strace -v -tt -T -o strace.sshd.log sshd -ddde" to get all the gory details and log to strace.sshd.log, or first add "-c" to only get an overview of time spent in syscalls when the app stops, maybe that'll help. I bet it's a resolving issue.

Excalibur · 04-13-2003, 09:29 PM

Could one end be attempting X11 forwarding but then failing on the other?

I have had similar experiences when logging in from stations with real world IP addresses that the ISP does not provide proper reverse mapping assignments. The system is attempting to do a reverse IP resolution and it can take some time just for it to fail. To test, add your station IP into the /etc/hosts file on the machine if it is static. You can also review the server logs and see if it was able to resolve your IP to a name.

It could also be attempting ssh2 authentication and then failing and falling back to ssh1, then finally asking for a password.

I have also experienced it with servers that are on a dialup gateway and they have other traffic using the bandwidth.

Review closely your /etc/ssh/sshd_config file. Perhaps something needs to be turned off or turned on.

Just some other possiblities to consider.