gitlab - ssh_exchange_identification: read: Connection reset by peer

Question

I am trying to clone from a Gitlab server from my Macbook. When I clone, I get the following error:

manzanita-226-109:icarus homeuser$ git clone elm:dummy/dummy.git
Cloning into 'dummy'...

ssh_exchange_identification: read: Connection reset by peer
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.

When I try to ssh into the gitlab server, I get the following:

OpenSSH_7.6p1, LibreSSL 2.6.2
debug1: Reading configuration data /Users/homeuser/.ssh/config
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 48: Applying options for *
debug1: Connecting to elm.ndc.nasa.gov port 22.
debug1: Connection established.
debug1: key_load_public: No such file or directory
debug1: identity file /Users/homeuser/.ssh/id_rsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /Users/homeuser/.ssh/id_rsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /Users/homeuser/.ssh/id_dsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /Users/homeuser/.ssh/id_dsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /Users/homeuser/.ssh/id_ecdsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /Users/homeuser/.ssh/id_ecdsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /Users/homeuser/.ssh/id_ed25519 type -1
debug1: key_load_public: No such file or directory
debug1: identity file /Users/homeuser/.ssh/id_ed25519-cert type -1
debug1: Local version string SSH-2.0-OpenSSH_7.6
ssh_exchange_identification: read: Connection reset by peer

I can get on the gitlab server using Google Chrome with no issues. I also tried cloning and ssh'ing from a different server with no issues. I do not have admin privileges on this gitlab server, but I do not believe there are any banning/blacklisting softwares on there.

Can anyone advise?

Answer 1

ssh_exchange_identification: read: Connection reset by peer

This basically means the TCP connection was "reset" immediately after being accepted by the server. Common reasons for this are:

• The remote SSH server software is malfunctioning (e.g. it crashed).
• The remote SSH server software is configured to drop your connections for some reason.
• Some router or other networking device between you and the server is interfering with the TCP connection.

There's no way to tell exactly what is wrong from the client debugging messages. You need to troubleshoot this on the server. The remote SSH server program might have a log file you can look at, for example.

Answer 2

On my server (Dockerized GitLab) the problem was that I had given the wrong permissions to sshd's keys in /etc/gitlab which could be seen by inspecting the logs in /var/log/gitlab/sshd.

I solved the problem by changing the permissions on the server with this command:

chmod -R 700 /etc/gitlab