Re: SSH connection failure: broken pipe

[Darren Tucker]

On 2/12/10 5:59 AM, Alex Popov wrote:

I just did a snapshot upgrade from 4.7-snapshot (Apr 7) to 4.8-snapshot (Nov
30)  and I can't establish outgoing SSH connections from this box. I noticed
the problem when I tried to update src and ports via cvs and got Read from
socket failed: Connection reset by peer error.


What's kind of weird is that both ends see reset by peer.  My guess is 
that it's some kind of network problem, either the network itself or the 
stack.  Does it fail immediately or does it take a while?  If it hangs 
for a while, try running netstat on each, identify the TCP connection 
and check if the send-q is non zero (indicating un-acked data).


--
Darren Tucker (dtucker at zip.com.au)
GPG key 8FF4FA69 / D9A3 86E9 7EEE AF4B B2D4  37C9 C982 80C7 8FF4 FA69
Good judgement comes with experience. Unfortunately, the experience
usually comes from bad judgement.

SSH connection failure: broken pipe

[Alex Popov]

Hi,

I just did a snapshot upgrade from 4.7-snapshot (Apr 7) to 4.8-snapshot (Nov
30)  and I can't establish outgoing SSH connections from this box. I noticed
the problem when I tried to update src and ports via cvs and got Read from
socket failed: Connection reset by peer error.

Then I tried establishing SSH connection to various hosts and they all are
failing before I get the login prompt. Here's the debug output from both
client and server:

Client:

$ ssh -v u...@host -p 8025
OpenSSH_5.6, OpenSSL 1.0.0a 1 Jun 2010
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Connecting to seidlitz.ca [209.205.80.77] port 8025.
debug1: Connection established.
debug1: identity file /home/apopov/.ssh/id_rsa type -1
debug1: identity file /home/apopov/.ssh/id_rsa-cert type -1
debug1: identity file /home/apopov/.ssh/id_dsa type -1
debug1: identity file /home/apopov/.ssh/id_dsa-cert type -1
debug1: identity file /home/apopov/.ssh/id_ecdsa type -1
debug1: identity file /home/apopov/.ssh/id_ecdsa-cert type -1
debug1: Remote protocol version 1.99, remote software version OpenSSH_4.3
debug1: match: OpenSSH_4.3 pat OpenSSH_4*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_5.6
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server-client aes128-ctr hmac-md5 none
debug1: kex: client-server aes128-ctr hmac-md5 none
debug1: SSH2_MSG_KEX_DH_GEX_REQUEST(102410248192) sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_GROUP
Read from socket failed: Connection reset by peer
$

Server:

$ sudo /usr/sbin/sshd -f /etc/ssh/sshd_config -p 8025 -d
debug1: sshd version OpenSSH_4.3
debug1: private host key: #0 type 0 RSA1
debug1: read PEM private key done: type RSA
debug1: private host key: #1 type 1 RSA
debug1: read PEM private key done: type DSA
debug1: private host key: #2 type 2 DSA
debug1: rexec_argv[0]='/usr/sbin/sshd'
debug1: rexec_argv[1]='-f'
debug1: rexec_argv[2]='/etc/ssh/sshd_config'
debug1: rexec_argv[3]='-p'
debug1: rexec_argv[4]='8025'
debug1: rexec_argv[5]='-d'
debug1: Bind to port 8025 on ::.
Server listening on :: port 8025.
debug1: Bind to port 8025 on 0.0.0.0.
Server listening on 0.0.0.0 port 8025.
Generating 768 bit RSA key.
RSA key generation complete.
debug1: fd 6 clearing O_NONBLOCK
debug1: Server will not fork when running in debugging mode.
debug1: rexec start in 6 out 6 newsock 6 pipe -1 sock 9
debug1: inetd sockets after dupping: 4, 4
Connection from 142.30.203.105 port 5459
debug1: Client protocol version 2.0; client software version OpenSSH_5.6
debug1: match: OpenSSH_5.6 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-1.99-OpenSSH_4.3
debug1: permanently_set_uid: 27/27
debug1: list_hostkey_types: ssh-rsa,ssh-dss
debug1: SSH2_MSG_KEXINIT sent
Read from socket failed: Connection reset by peer
debug1: do_cleanup
debug1: do_cleanup
$

Any ideas what may be causing it?

Thanks,

Alex