FWIW if I try the same command I get all the way through to a normal exit (which I guess is expected since you're not supposed to be able to actually obtain a shell via ssh!) so I guess the problem is specific to you, Simon. Tom OpenSSH_8.4p1 Debian-5+deb11u1, OpenSSL 1.1.1n 15 Mar 2022 debug1: Reading configuration data /home/tom/.ssh/config debug1: Reading configuration data /etc/ssh/ssh_config debug1: /etc/ssh/ssh_config line 19: include /etc/ssh/ssh_config.d/*.conf matched no files debug1: /etc/ssh/ssh_config line 21: Applying options for * debug1: Connecting to gitlab.haskell.org [2604:1380:61:2300::1] port 22. debug1: Connection established. debug1: identity file <redacted> debug1: Local version string SSH-2.0-OpenSSH_8.4p1 Debian-5+deb11u1 debug1: Remote protocol version 2.0, remote software version OpenSSH_9.1 debug1: match: OpenSSH_9.1 pat OpenSSH* compat 0x04000000 debug1: Authenticating to gitlab.haskell.org:22 as 'git' debug1: SSH2_MSG_KEXINIT sent debug1: SSH2_MSG_KEXINIT received debug1: kex: algorithm: curve25519-sha256 debug1: kex: host key algorithm: ssh-ed25519 debug1: kex: server->client cipher: chacha20-poly1305@openssh.com MAC: <implicit> compression: none debug1: kex: client->server cipher: chacha20-poly1305@openssh.com MAC: <implicit> compression: none debug1: expecting SSH2_MSG_KEX_ECDH_REPLY debug1: Server host key: ssh-ed25519 SHA256:/dI7zsBRZNPB+0TqskF7rSaZ/LhQw0cF4c5W+4uMlRo debug1: Host 'gitlab.haskell.org' is known and matches the ED25519 host key. debug1: Found key in <redacted> debug1: rekey out after 134217728 blocks debug1: SSH2_MSG_NEWKEYS sent debug1: expecting SSH2_MSG_NEWKEYS debug1: SSH2_MSG_NEWKEYS received debug1: rekey in after 134217728 blocks debug1: Will attempt key: <redacted> debug1: SSH2_MSG_EXT_INFO received debug1: kex_input_ext_info: server-sig-algs= debug1: kex_input_ext_info: publickey-hostbound@openssh.com (unrecognised) debug1: SSH2_MSG_SERVICE_ACCEPT received debug1: Authentications that can continue: publickey,password,keyboard-interactive debug1: Next authentication method: publickey debug1: Offering public key: <redacted> debug1: Authentications that can continue: publickey,password,keyboard-interactive debug1: Offering public key: <redacted> debug1: Server accepts key: <redacted> debug1: Authentication succeeded (publickey). Authenticated to gitlab.haskell.org ([2604:1380:61:2300::1]:22). debug1: channel 0: new [client-session] debug1: Requesting no-more-sessions@openssh.com debug1: Entering interactive session. debug1: pledge: network debug1: client_input_global_request: rtype hostkeys-00@openssh.com want_reply 0 debug1: Remote: /var/gitlab/state/home/.ssh/authorized_keys:857: key options: command user-rc debug1: Remote: /var/gitlab/state/home/.ssh/authorized_keys:857: key options: command user-rc debug1: Sending environment. debug1: Sending env LANG = en_GB.UTF-8 PTY allocation request failed on channel 0 Welcome to GitLab, @tomjaguarpaw1! debug1: client_input_channel_req: channel 0 rtype exit-status reply 0 debug1: client_input_channel_req: channel 0 rtype eow@openssh.com reply 0 debug1: channel 0: free: client-session, nchannels 1 Connection to gitlab.haskell.org closed. Transferred: sent 3296, received 2832 bytes, in 0.4 seconds Bytes per second: sent 9134.7, received 7848.7 debug1: Exit status 0 On Thu, Jun 22, 2023 at 11:15:28AM +0100, Simon Peyton Jones wrote:

Is SSH working on gitlab.haskell.org? I'm getting this

simonpj@CDW-8FABODHF0V5:~$ ssh -v git@gitlab.haskell.org OpenSSH_8.2p1 Ubuntu-4, OpenSSL 1.1.1f 31 Mar 2020 debug1: Reading configuration data /home/simonpj/.ssh/config debug1: Reading configuration data /etc/ssh/ssh_config debug1: /etc/ssh/ssh_config line 19: include /etc/ssh/ssh_config.d/*.conf matched no files debug1: /etc/ssh/ssh_config line 21: Applying options for * debug1: Connecting to gitlab.haskell.org [145.40.64.137] port 22. debug1: Connection established. debug1: identity file /home/simonpj/.ssh/id_rsa type 0 debug1: identity file /home/simonpj/.ssh/id_rsa-cert type -1 debug1: identity file /home/simonpj/.ssh/id_dsa type 1 debug1: identity file /home/simonpj/.ssh/id_dsa-cert type -1 debug1: identity file /home/simonpj/.ssh/id_ecdsa type -1 debug1: identity file /home/simonpj/.ssh/id_ecdsa-cert type -1 debug1: identity file /home/simonpj/.ssh/id_ecdsa_sk type -1 debug1: identity file /home/simonpj/.ssh/id_ecdsa_sk-cert type -1 debug1: identity file /home/simonpj/.ssh/id_ed25519 type 3 debug1: identity file /home/simonpj/.ssh/id_ed25519-cert type -1 debug1: identity file /home/simonpj/.ssh/id_ed25519_sk type -1 debug1: identity file /home/simonpj/.ssh/id_ed25519_sk-cert type -1 debug1: identity file /home/simonpj/.ssh/id_xmss type -1 debug1: identity file /home/simonpj/.ssh/id_xmss-cert type -1 debug1: Local version string SSH-2.0-OpenSSH_8.2p1 Ubuntu-4

At this point it hangs. Stackoverflow suggests https://superuser.com/questions/1374076/what-does-it-mean-if-ssh-hangs-after...a server fault. But I'm on a new WLAN so I suppose there could be some bizarre filtering?

Simon Peyton Jones writes:

Is SSH working on gitlab.haskell.org? I'm getting this

simonpj@CDW-8FABODHF0V5:~$ ssh -v git@gitlab.haskell.org OpenSSH_8.2p1 Ubuntu-4, OpenSSL 1.1.1f 31 Mar 2020 debug1: Reading configuration data /home/simonpj/.ssh/config debug1: Reading configuration data /etc/ssh/ssh_config debug1: /etc/ssh/ssh_config line 19: include /etc/ssh/ssh_config.d/*.conf matched no files debug1: /etc/ssh/ssh_config line 21: Applying options for * debug1: Connecting to gitlab.haskell.org [145.40.64.137] port 22. debug1: Connection established. debug1: identity file /home/simonpj/.ssh/id_rsa type 0 debug1: identity file /home/simonpj/.ssh/id_rsa-cert type -1 debug1: identity file /home/simonpj/.ssh/id_dsa type 1 debug1: identity file /home/simonpj/.ssh/id_dsa-cert type -1 debug1: identity file /home/simonpj/.ssh/id_ecdsa type -1 debug1: identity file /home/simonpj/.ssh/id_ecdsa-cert type -1 debug1: identity file /home/simonpj/.ssh/id_ecdsa_sk type -1 debug1: identity file /home/simonpj/.ssh/id_ecdsa_sk-cert type -1 debug1: identity file /home/simonpj/.ssh/id_ed25519 type 3 debug1: identity file /home/simonpj/.ssh/id_ed25519-cert type -1 debug1: identity file /home/simonpj/.ssh/id_ed25519_sk type -1 debug1: identity file /home/simonpj/.ssh/id_ed25519_sk-cert type -1 debug1: identity file /home/simonpj/.ssh/id_xmss type -1 debug1: identity file /home/simonpj/.ssh/id_xmss-cert type -1 debug1: Local version string SSH-2.0-OpenSSH_8.2p1 Ubuntu-4

At this point it hangs. Stackoverflow suggests https://superuser.com/questions/1374076/what-does-it-mean-if-ssh-hangs-after...a server fault. But I'm on a new WLAN so I suppose there could be some bizarre filtering?

I suspect this may be a filtering issue. Like Tom, I am able to connect without issue. A Wireshark trace [1] may help shed light on the situation. Happy to have a call to debug if this would be helpful. Cheers, - Ben [1] https://www.wireshark.org/