[gentoo-user] ssh stalls - please help

[gentoo-user] ssh stalls - please help

[Helmut Jarausch]

Hi,

probably since I've emerged openssh-6.0_p1 and/or git-sources-3.4_rc? I  
have problems with ssh.
scp as well as filezilla as well as  rsync -e 'ssh' stall when  
transmitting a somewhat larger file.
This might be as few as 500 Kb on a slow network (256 Kbit/s).
But it occurs on a fast network (100 Mbit/s) as well, when transmitting  
a larger file.

ssh not only stalls but seems to hang indefinitely.

Is this bug known and is there a work around?

Many thanks for some help,
Helmut.

Re: [gentoo-user] ssh stalls - please help

[Keith Dart]

Re , Helmut Jarausch said:
> Is this bug known and is there a work around?

Sorry no answer, but I also saw this when using scp. I wasn't sure what
it was. But you're not alone... ;-)

Maybe we should just downgrade?


-- Keith


-- 

-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   Keith Dart <keith@dartworks.biz>
   public key: ID: 19017044
   <http://www.dartworks.biz/>
   =====================================================================

Re: [gentoo-user] ssh stalls - please help

[Neil Bothwick]

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On Tue, 08 May 2012 09:04:59 +0200, Helmut Jarausch wrote:

> probably since I've emerged openssh-6.0_p1 and/or git-sources-3.4_rc?
> I have problems with ssh.
> scp as well as filezilla as well as  rsync -e 'ssh' stall when  
> transmitting a somewhat larger file.
> This might be as few as 500 Kb on a slow network (256 Kbit/s).
> But it occurs on a fast network (100 Mbit/s) as well, when
> transmitting a larger file.
> 
> ssh not only stalls but seems to hang indefinitely.

Yes it is, search b.g.o.

The problem is caused by the server running openssh-0.6_p1 with the hpn
USE flag, which is enabled by default. Either downgrade to 5.x or
re-emerge with USE="-hpn". I did the latter and everything is working as
it should now.

Well, not everything, my knee is still shot but SSH works :(


-- 
Neil Bothwick

mandelbug /man'del-buhg/ n.
 [from the Mandelbrot set] A
   bug whose underlying causes are so complex and obscure as to make
   its behavior appear chaotic or even non-deterministic.  This term
   implies that the speaker thinks it is a Bohr bug, rather than
   a heisenbug.  See also schroedinbug.

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Re: [gentoo-user] ssh stalls - please help

[Joseph]

On 05/08/12 09:09, Neil Bothwick wrote:
>On Tue, 08 May 2012 09:04:59 +0200, Helmut Jarausch wrote:
>
>> probably since I've emerged openssh-6.0_p1 and/or git-sources-3.4_rc?
>> I have problems with ssh.
>> scp as well as filezilla as well as  rsync -e 'ssh' stall when
>> transmitting a somewhat larger file.
>> This might be as few as 500 Kb on a slow network (256 Kbit/s).
>> But it occurs on a fast network (100 Mbit/s) as well, when
>> transmitting a larger file.
>>
>> ssh not only stalls but seems to hang indefinitely.

Well, openssh-5.9_p1-r4 
flag: "hpn" on by default and ssh is working without a problem.

If I were you I would open a bug.

-- 
Joseph

Re: [gentoo-user] ssh stalls - please help

[Keith Dart]

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Re 1336460699.6491.0@numa-i1336460699.6491.0@numa-i, Neil Bothwick said:
> re-emerge with USE="-hpn". I did the latter and everything is working
> as it should now.


Funny how "hpn" is supposed to enable "high performance". :-D

-- Keith


-- 

-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   Keith Dart <keith@dartworks.biz>
   public key: ID: 19017044
   <http://www.dartworks.biz/>
   =====================================================================

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Re: [gentoo-user] ssh stalls - please help

[Neil Bothwick]

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On Tue, 8 May 2012 11:29:19 -0700, Keith Dart wrote:

> > re-emerge with USE="-hpn". I did the latter and everything is working
> > as it should now.  

> Funny how "hpn" is supposed to enable "high performance". :-D

But it stalls and blocks so much more quickly with it on :)


-- 
Neil Bothwick

Mr. bullfrog says: "time's fun when you're having flies."

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Re: [gentoo-user] ssh stalls - please help

[Neil Bothwick]

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On Tue, 8 May 2012 12:09:05 -0600, Joseph wrote:

> Well, openssh-5.9_p1-r4 
> flag: "hpn" on by default and ssh is working without a problem.

It's only a problem with hpn and openssh-6.0_p1, as discussed in the bug
report.

> If I were you I would open a bug.

Another one?


-- 
Neil Bothwick

Committee (noun): A group of people spending hours taking minutes

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Re: [gentoo-user] ssh stalls - please help

[Neil Bothwick]

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On Tue, 8 May 2012 09:09:28 +0100, Neil Bothwick wrote:

> The problem is caused by the server running openssh-0.6_p1 with the hpn
> USE flag, which is enabled by default. Either downgrade to 5.x or
> re-emerge with USE="-hpn". I did the latter and everything is working as
> it should now.

The bug report at https://bugs.gentoo.org/show_bug.cgi?id=414401 now
contains another solution. Leave hpn enabled but set TcpRcvBufPoll to no
in sshd_config. I've tried this and it seems to work. Now we just need to
find which kernel option to set to get this to work properly.


-- 
Neil Bothwick

I know corn oil comes from corn, where does baby oil come from?

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Re: [gentoo-user] ssh stalls - please help

[Helmut Jarausch]

On 05/09/2012 11:56:45 AM, Neil Bothwick wrote:
> On Tue, 8 May 2012 09:09:28 +0100, Neil Bothwick wrote:
> 
> > The problem is caused by the server running openssh-0.6_p1 with the  
> hpn
> > USE flag, which is enabled by default. Either downgrade to 5.x or
> > re-emerge with USE="-hpn". I did the latter and everything is  
> working as
> > it should now.
> 
> The bug report at https://bugs.gentoo.org/show_bug.cgi?id=414401 now
> contains another solution. Leave hpn enabled but set TcpRcvBufPoll to  
> no
> in sshd_config. I've tried this and it seems to work. Now we just  
> need to
> find which kernel option to set to get this to work properly.
> 
Sorry, but I don't this. You say, it works without changing any kernel  
configuration.
So, why
"Now we just need to find which kernel option to set to get this to  
work properly."

Helmut.

Re: [gentoo-user] ssh stalls - please help

[Neil Bothwick]

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On Wed, 09 May 2012 13:29:26 +0200, Helmut Jarausch wrote:

> > The bug report at https://bugs.gentoo.org/show_bug.cgi?id=414401 now
> > contains another solution. Leave hpn enabled but set TcpRcvBufPoll
> > to no
> > in sshd_config. I've tried this and it seems to work. Now we just  
> > need to
> > find which kernel option to set to get this to work properly.
> >   
> Sorry, but I don't this. You say, it works without changing any kernel  
> configuration.
> So, why
> "Now we just need to find which kernel option to set to get this to  
> work properly."

The comment for that configuration option states "# tcp receive buffer
polling. disable in non autotuning kernels". Setting it to no makes it
work, but the implication is that there is a kernel option that will work
with the default.


-- 
Neil Bothwick

"RAM DISK is NOT an installation procedure!"

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[gentoo-user] Re: ssh stalls - please help

[James]

Helmut Jarausch <jarausch <at> igpm.rwth-aachen.de> writes:


> probably since I've emerged openssh-6.0_p1 and/or git-sources-3.4_rc? I  
> have problems with ssh.

Well, I have a new problem with ssh too. I'm curious if my
problem is related to Helmut's; thus posting in his thread.


When I set up a new Adtran router, I give the router a local
ip and I can ssh into it without issue (over the ethernet).

When I put the router across a frame relay network, it
gives a protocol timeout error [1]. I have many older
antran routers where the same version of openssh works without 
issue; and the (allocated) bandwidth is the same. I have 
an open ticket with adtran, as they are looking at
the problem from their end and admit some issues with
their latest firmware, particularly related to cisco 
compatibility.

Here is how the openssh is setup on my laptop:
net-misc/openssh-5.9_p1-r4  USE="X hpn ldap pam tcpd 

So I guess I can recompile this 5.9 version of openssh (-hpn) and 
and test it out (several days round trip travel time will
elapse). The FR circuit is limited to 16Kbps
on the segment where the problem exist. Segements with older
adtran routers on 16 Kbps links are work just fine.
Is there a way to relax the timing on the protocol
negotiations, so as to make the new Adtran's more
tolerant? I guess Adtran would have to do this, or
can I pass some options via openssh or another version
of ssh?

So another questions is this. Is there another older ssh (version 2
support) laying around in portage (or elsewhere) I should try?
Maybe another "ssh" is more relaxed on timeout issues?
Remember, I'm an old unix_hack so I keep things like very
old versions of telnet(and many others) around, to access 
old (like me) equipment.....

I even used a command line option to specify the encryption,
"3des-cbc"  but I get the same error message.

Ideas, comments and syntax suggestions are welcome.

James

[1]
OpenSSH_5.9p1-hpn13v11lpk, OpenSSL 1.0.0i 19 Apr 2012
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Connecting to 192.168.21.2 [192.168.21.2] port 22.
debug1: Connection established.
debug1: identity file /home/james/.ssh/id_rsa type -1
debug1: identity file /home/james/.ssh/id_rsa-cert type -1
debug1: identity file /home/james/.ssh/id_dsa type -1
debug1: identity file /home/james/.ssh/id_dsa-cert type -1
debug1: identity file /home/james/.ssh/id_ecdsa type -1
debug1: identity file /home/james/.ssh/id_ecdsa-cert type -1
debug1: Remote protocol version 2.0, remote software version RomSShell_4.31
debug1: no match: RomSShell_4.31
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_5.9p1-hpn13v11lpk
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: AUTH STATE IS 0
debug1: REQUESTED ENC.NAME is '3des-cbc'
debug1: kex: server->client 3des-cbc hmac-sha1 none
debug1: REQUESTED ENC.NAME is '3des-cbc'
debug1: kex: client->server 3des-cbc hmac-sha1 none
debug1: sending SSH2_MSG_KEXDH_INIT
debug1: expecting SSH2_MSG_KEXDH_REPLY
Received disconnect from 192.168.21.2: 2: Protocol Timeout