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When I try to ssh this in a terminal: ssh username@sub.domain.com I get the following error:
Connection closed by

When I use putty, I am able to connect to the server. Why is this happening, and how can I get this to work in a terminal?

ssh -v username@sub.domain.com

OpenSSH_6.0p1 (CentrifyDC build 5.1.0-472) (CentrifyDC build 5.1.0-472), OpenSSL 0.9.8w 23 Apr 2012
debug1: Reading configuration data /etc/centrifydc/ssh/ssh_config
debug1: /etc/centrifydc/ssh/ssh_config line 52: Applying options for *
debug1: Connecting to sub.domain.com [] port 22.
debug1: Connection established.
debug1: identity file /home/ryannaddy/.ssh/id_rsa type -1
debug1: identity file /home/ryannaddy/.ssh/id_rsa-cert type -1
debug1: identity file /home/ryannaddy/.ssh/id_dsa type -1
debug1: identity file /home/ryannaddy/.ssh/id_dsa-cert type -1
debug1: identity file /home/ryannaddy/.ssh/id_ecdsa type -1
debug1: identity file /home/ryannaddy/.ssh/id_ecdsa-cert type -1
debug1: Remote protocol version 2.0, remote software version OpenSSH_5.1p1 Debian-5
debug1: match: OpenSSH_5.1p1 Debian-5 pat OpenSSH_5*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_6.0
debug1: Miscellaneous failure
Cannot resolve network address for KDC in requested realm

debug1: Miscellaneous failure
Cannot resolve network address for KDC in requested realm

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(1024<1024<8192) sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_GROUP
Connection closed by
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What does ssh -v username@sub.domain.com show? –  James Sneeringer Mar 20 '13 at 13:58
I updated the main question. Also the server should ask for a password, there are no ssh keys required to login. –  Ryan Naddy Mar 20 '13 at 14:10
Did you change any settings from default in PuTTY? –  Kruug Mar 20 '13 at 14:15
Also, have you tried user@domain.com? Leave out the sub. –  Kruug Mar 20 '13 at 14:16
You're using Centrify's build of OpenSSH, which implies your system is AD-integrated. Active Directory uses Kerberos, and OpenSSH is complaining that it can't find the Kerberos KDC, so it's bailing out. What does your /etc/krb5.conf look like? –  James Sneeringer Mar 20 '13 at 14:33

3 Answers 3

Solution found for me via the following URL: http://www.held.org.il/blog/2011/05/the-myterious-case-of-broken-ssh-client-connection-reset-by-peer/

It even does a pretty good job of explaining what is going on.

Ultimately, I added the following to /etc/ssh/ssh_config:

Host *
SendEnv LANG LC_*
HashKnownHosts yes
GSSAPIAuthentication yes
GSSAPIDelegateCredentials no
Ciphers aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc
HostKeyAlgorithms ssh-rsa,ssh-dss
MACs hmac-md5,hmac-sha1,hmac-ripemd160

Neither Ciphers, or HostKeyAlgorithms worked on their own, pretty sure MACs put me over the top to get this to work, but I can't be sure, put many hours into getting this solved. I hope this can at least help somebody else.

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thanks, in my case just the last line MACs hmac-md5,hmac-sha1,hmac-ripemd160 was enough –  Tombart Dec 10 '13 at 22:14
I had a problem with github - git pull / git push - nothing happened. Tried ssh -T -v git@github.com and got the same error. Used this to solve it. Thank you! –  Jason Jan 9 at 23:21
I had a similar problem and tried this solution. One side effect is that any connection to a known host would then accuse a host key change. –  lfagundes Feb 28 at 15:18

Did some looking and found the following suggestion here:

Try making sure the following line in your /etc/ssh/ssh_config (NOT sshd_config) is NOT commented out:

Ciphers aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc

You also might try reverting that file back to the default and trying again, i.e. uninstall and reinstall openssh-client IIRC the name of the package.

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That didn't fix it :( –  Ryan Naddy Mar 20 '13 at 15:04

This worked for me ...

ifconfig eth0 mtu 576


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