Re: Can't connect with ssh
On 17 Wrz, 21:21, Ryszard Mikke <Ryszard.Mi...@gmail.com> wrote:[color=blue]
> Ummm... That one is strange:
>
> I can't login via ssh on one of my machines.
>
> ssh asks for a password then hangs, i can't even get out of it with
> Ctrl-C or ctrl-D.
> I can login via telnet to it with no problem.
> I have checked, that there is no firewall problem by trying to ssh
> from a machine
> that is in the same zone (no firewall between them) - the problem
> occurs as well.
>
> So I have tried to restart sshd, but the problem remains.
>
> The sessions connected via ssh before the problem occured, still work.
>
> What else can I do without restarting the machine?
>
> The oslevel is 4330-10[/color]
Well, killing ALL the sshd processes has helped.
But I would still like to know if I could do it without killing users'
sessions...
rmikke
Re: Can't connect with ssh
Ryszard Mikke schrieb:
[color=blue]
>
> Well, killing ALL the sshd processes has helped.
> But I would still like to know if I could do it without killing users'
> sessions...[/color]
just a wild guess: how about machine is running out of resources,
i.e. # of processes allowed per user ?
Re: Can't connect with ssh
On 18 Wrz, 00:16, Michael Kraemer <M.Krae...@gsi.de> wrote:[color=blue]
> Ryszard Mikke schrieb:
>
>
>[color=green]
> > Well, killing ALL the sshd processes has helped.
> > But I would still like to know if I could do it without killing users'
> > sessions...[/color]
>
> just a wild guess: how about machine is running out of resources,
> i.e. # of processes allowed per user ?[/color]
Nope. Checked that, not even close to limit set in SMIT.
Maybe some other resource I didn't think of, but then, why can I login
with telnet
and not with ssh?
rmikke
Re: Can't connect with ssh
On 17 Wrz, 22:42, Ryszard Mikke <Ryszard.Mi...@gmail.com> wrote:[color=blue]
> On 17 Wrz, 21:21, Ryszard Mikke <Ryszard.Mi...@gmail.com> wrote:
>
>
>[color=green]
> > Ummm... That one is strange:[/color]
>[color=green]
> > I can't login via ssh on one of my machines.[/color]
>[color=green]
> > ssh asks for a password then hangs, i can't even get out of it with
> > Ctrl-C or ctrl-D.
> > I can login via telnet to it with no problem.
> > I have checked, that there is no firewall problem by trying to ssh
> > from a machine
> > that is in the same zone (no firewall between them) - the problem
> > occurs as well.[/color]
>[color=green]
> > So I have tried to restart sshd, but the problem remains.[/color]
>[color=green]
> > The sessions connected via ssh before the problem occured, still work.[/color]
>[color=green]
> > What else can I do without restarting the machine?[/color]
>[color=green]
> > The oslevel is 4330-10[/color]
>
> Well, killing ALL the sshd processes has helped.
> But I would still like to know if I could do it without killing users'
> sessions...[/color]
Sh*t, @#%$^%#!!, again.
Any ideas as to the reason of this happening?
rmikke
Re: Can't connect with ssh
On 18 Wrz, 00:42, Ryszard Mikke <Ryszard.Mi...@gmail.com> wrote:[color=blue]
> On 17 Wrz, 22:42, Ryszard Mikke <Ryszard.Mi...@gmail.com> wrote:
>
>
>[color=green]
> > On 17 Wrz, 21:21, Ryszard Mikke <Ryszard.Mi...@gmail.com> wrote:[/color]
>[color=green][color=darkred]
> > > Ummm... That one is strange:[/color][/color]
>[color=green][color=darkred]
> > > I can't login via ssh on one of my machines.[/color][/color]
>[color=green][color=darkred]
> > > ssh asks for a password then hangs, i can't even get out of it with
> > > Ctrl-C or ctrl-D.
> > > I can login via telnet to it with no problem.
> > > I have checked, that there is no firewall problem by trying to ssh
> > > from a machine
> > > that is in the same zone (no firewall between them) - the problem
> > > occurs as well.[/color][/color]
>[color=green][color=darkred]
> > > So I have tried to restart sshd, but the problem remains.[/color][/color]
>[color=green][color=darkred]
> > > The sessions connected via ssh before the problem occured, still work.[/color][/color]
>[color=green][color=darkred]
> > > What else can I do without restarting the machine?[/color][/color]
>[color=green][color=darkred]
> > > The oslevel is 4330-10[/color][/color]
>[color=green]
> > Well, killing ALL the sshd processes has helped.
> > But I would still like to know if I could do it without killing users'
> > sessions...[/color]
>
> Sh*t, @#%$^%#!!, again.
>
> Any ideas as to the reason of this happening?[/color]
Errpt says nothing, netstat shows these sessions as ESTABLISHED. I
just don't get prompt...
rmikke
Re: Can't connect with ssh
Ryszard Mikke wrote:[color=blue]
> On 18 Wrz, 00:42, Ryszard Mikke <Ryszard.Mi...@gmail.com> wrote:[color=green]
>> On 17 Wrz, 22:42, Ryszard Mikke <Ryszard.Mi...@gmail.com> wrote:
>>
>>
>>[color=darkred]
>>> On 17 Wrz, 21:21, Ryszard Mikke <Ryszard.Mi...@gmail.com> wrote:
>>>> Ummm... That one is strange:
>>>> I can't login via ssh on one of my machines.
>>>> ssh asks for a password then hangs, i can't even get out of it with
>>>> Ctrl-C or ctrl-D.
>>>> I can login via telnet to it with no problem.
>>>> I have checked, that there is no firewall problem by trying to ssh
>>>> from a machine
>>>> that is in the same zone (no firewall between them) - the problem
>>>> occurs as well.
>>>> So I have tried to restart sshd, but the problem remains.
>>>> The sessions connected via ssh before the problem occured, still work.
>>>> What else can I do without restarting the machine?
>>>> The oslevel is 4330-10
>>> Well, killing ALL the sshd processes has helped.
>>> But I would still like to know if I could do it without killing users'
>>> sessions...[/color]
>> Sh*t, @#%$^%#!!, again.
>>
>> Any ideas as to the reason of this happening?[/color]
>
> Errpt says nothing, netstat shows these sessions as ESTABLISHED. I
> just don't get prompt...
>
> rmikke
>[/color]
use truss -fp <pid> on the ssh daemon process then connect again. this
should give some clue on what is happening.
Joachim Gann
Re: Can't connect with ssh
Joachim Gann wrote:[color=blue]
> Ryszard Mikke wrote:[/color]
[color=blue][color=green][color=darkred]
>>>>> The oslevel is 4330-10[/color][/color][/color]
[color=blue]
>[/color]
ah well, no luck. truss was introduced in aix 5.2
Re: Can't connect with ssh
Joachim Gann wrote:[color=blue]
> Joachim Gann wrote:[color=green]
>> Ryszard Mikke wrote:[/color]
>[color=green][color=darkred]
>>>>>> The oslevel is 4330-10[/color][/color]
>
>
> ah well, no luck. truss was introduced in aix 5.2[/color]
Were there any clues in the SSH log?
Re: Can't connect with ssh
Ryszard Mikke pisze:[color=blue]
> On 17 Wrz, 22:42, Ryszard Mikke <Ryszard.Mi...@gmail.com> wrote:
>
> Sh*t, @#%$^%#!!, again.
>
> Any ideas as to the reason of this happening?[/color]
Ryszard try to put sshd into debug mode and watch syslog.
--
Regards
Filip Kata
Re: Can't connect with ssh
On Sep 17, 2:21 pm, Ryszard Mikke <Ryszard.Mi...@gmail.com> wrote:[color=blue]
> Ummm... That one is strange:
>
> I can't login via ssh on one of my machines.
>
> ssh asks for a password then hangs, i can't even get out of it with
> Ctrl-C or ctrl-D.
> I can login via telnet to it with no problem.
> I have checked, that there is no firewall problem by trying to ssh
> from a machine
> that is in the same zone (no firewall between them) - the problem
> occurs as well.
>
> So I have tried to restart sshd, but the problem remains.
>
> The sessions connected via ssh before the problem occured, still work.
>
> What else can I do without restarting the machine?
>
> The oslevel is 4330-10[/color]
As someone already mentioned, watch syslog.
I often find that permissions cause problems with ssh. Especially the
perms on your home directory.
Miles
Re: Can't connect with ssh
On Sep 17, 4:21 pm, Ryszard Mikke <Ryszard.Mi...@gmail.com> wrote:[color=blue]
> Ummm... That one is strange:
>
> I can't login via ssh on one of my machines.
>
> ssh asks for a password then hangs, i can't even get out of it with
> Ctrl-C or ctrl-D.
> I can login via telnet to it with no problem.
> I have checked, that there is no firewall problem by trying to ssh
> from a machine
> that is in the same zone (no firewall between them) - the problem
> occurs as well.
>
> So I have tried to restart sshd, but the problem remains.
>
> The sessions connected via ssh before the problem occured, still work.
>
> What else can I do without restarting the machine?
>
> The oslevel is 4330-10[/color]
You need to check how the ssh is authenticating users. PAM, keyboard
authentication and stuff like that. Run a ssh -vvv user@hostname from
your computer to the server and see which authentication steps are
made and which failed.
Re: Can't connect with ssh
On Sep 18, 11:56 am, Emerson Seiti Takahashi <ese...@gmail.com> wrote:[color=blue]
> On Sep 17, 4:21 pm, Ryszard Mikke <Ryszard.Mi...@gmail.com> wrote:
>
>
>[color=green]
> > Ummm... That one is strange:[/color]
>[color=green]
> > I can't login via ssh on one of my machines.[/color]
>[color=green]
> > ssh asks for a password then hangs, i can't even get out of it with
> > Ctrl-C or ctrl-D.
> > I can login via telnet to it with no problem.
> > I have checked, that there is no firewall problem by trying to ssh
> > from a machine
> > that is in the same zone (no firewall between them) - the problem
> > occurs as well.[/color]
>[color=green]
> > So I have tried to restart sshd, but the problem remains.[/color]
>[color=green]
> > The sessions connected via ssh before the problem occured, still work.[/color]
>[color=green]
> > What else can I do without restarting the machine?[/color]
>[color=green]
> > The oslevel is 4330-10[/color]
>
> You need to check how the ssh is authenticating users. PAM, keyboard
> authentication and stuff like that. Run a ssh -vvv user@hostname from
> your computer to the server and see which authentication steps are
> made and which failed.[/color]
try to run in debbug mode ... and connect with ssh from the same
machine ...
mymachine> ssh mymachine
---
other options
re-install ssh
Re: Can't connect with ssh
On Sep 18, 7:21 am, Ryszard Mikke <Ryszard.Mi...@gmail.com> wrote:[color=blue]
> Ummm... That one is strange:
>
> I can't login via ssh on one of my machines.
>
> ssh asks for a password then hangs, i can't even get out of it with
> Ctrl-C or ctrl-D.
> I can login via telnet to it with no problem.
> I have checked, that there is no firewall problem by trying to ssh
> from a machine
> that is in the same zone (no firewall between them) - the problem
> occurs as well.
>
> So I have tried to restart sshd, but the problem remains.
>
> The sessions connected via ssh before the problem occured, still work.
>
> What else can I do without restarting the machine?
>
> The oslevel is 4330-10[/color]
also check your DNS lookups
and post your solution :)
Re: Can't connect with ssh
[color=blue]
> also check your DNS lookups
>
> and post your solution :)- Hide quoted text -
>
> - Show quoted text -[/color]
My dollar is on bad reverse-DNS lookups. Our DNS here is not handled
by the UNIX team, and the staff that handles it is not necessarily
fully up to speed with the intricacies of split-horizon DNS, and so a
lot of reverse lookups get sent out to neverneverland, which causes
SSH to hang indefinitely, until all resolvers are tried.
You may find releif in "UseDNS No" in the sshd_config file.
mjc
--
Mark J. Cecil -- Senior UNIX Engineer and Part-time Curmudgeon
New Orleans, Louisiana
[url]http://notrealswift.blogspot.com[/url]
"La Nouvelle-Orleans... Maintenant et pour toujours"
Re: Can't connect with ssh
Another possibility that causes hang situations is the inability to
mount the user's home directory.
Running AIX trace on the system you're logging into, and stopping it
when you get blocked
might expose some things going wrong that are difficult to diagnose.
It will reveal things like
reverse-DNS, mounting problems, etc.
