tmate : Error connecting: Socket error: disconnected

[alnhk]

We are using this docker image - tmate/tmate-ssh-server:latest, and started on kubernetes using below

        - name: HAS_WEBSOCKET
          value: "0"
        - name: USE_PROXY_PROTOCOL
          value: "1"
        - name: SSH_HOSTNAME
          value: "localhost"
        - name: SSH_PORT_LISTEN
          value: "2224"
        - name: SSH_KEYS_PATH
          value: "/etc/tmate-keys"

And also started kubernetes service with load balancer. On the other machines, we configured to have ~/.tmate.conf to have this value :

set -g tmate-server-host af40f9f34d8b04b5df19dc9a7632-1754039.us-west-2.elb.amazonaws.com
set -g tmate-server-port 2224
set  tmate-authorized-keys "~/.ssh/authorized_keys"

on kubernetes pod where tmate/tmate-ssh-server:latest is running, it shows this :

Loading key /etc/tmate-keys/ssh_host_rsa_key
Accepting connections on :2224

However, when we trigger "tmate -F" from other machine, we encounter this below issue , we are using latest 2.4.0 as tmate version:

Error connecting: Socket error: disconnected
Reconnecting...
Connecting to af40f9f34d8b04b5df19dc9a7632-1754039.us-west-2.elb.amazonaws.com...
Error connecting: Socket error: disconnected
Reconnecting...
Connecting to af40f9f34d8b04b5df19dc9a7632-1754039.us-west-2.elb.amazonaws.com...
Error connecting: Socket error: disconnected
Reconnecting...
Connecting to af40f9f34d8b04b5df19dc9a7632-1754039.us-west-2.elb.amazonaws.com...
Error connecting: Socket error: disconnected
Reconnecting...
Connecting to af40f9f34d8b04b5df19dc9a7632-1754039.us-west-2.elb.amazonaws.com...
Error connecting: Socket error: disconnected
Reconnecting...
Connecting to af40f9f34d8b04b5df19dc9a7632-1754039.us-west-2.elb.amazonaws.com...
cError connecting: Socket error: disconnected

Can any one please share what exactly cause this issue but when we test using telnet, it goes fine :

telnet af40f9f34d8b04b5df19dc9a7632-1754039.us-west-2.elb.amazonaws.com 2224
Trying 24.118.90.163...
Connected to af40f9f34d8b04b5df19dc9a7632-1754039.us-west-2.elb.amazonaws.com.
Escape character is '^]'.

[alnhk]

Further debug logs when executing "tmate -F -x"

Looking up af40f9f34d8b04b5df19dc9a7632-1754039.us-west-2.elb.amazonaws.com...
Connecting to af40f9f34d8b04b5df19dc9a7632-1754039.us-west-2.elb.amazonaws.com...
[1] [local_parse_file] local_parse_file: Cannot find file ssh_config.d/* to load
[2] [ssh_config_parse_line] ssh_config_parse_line: Unapplicable option: ForwardX11Trusted, line: 63
[2] [ssh_config_parse_line] ssh_config_parse_line: Unapplicable option: SendEnv, line: 65
[2] [ssh_config_parse_line] ssh_config_parse_line: Unapplicable option: SendEnv, line: 66
[2] [ssh_config_parse_line] ssh_config_parse_line: Unapplicable option: SendEnv, line: 67
[2] [ssh_config_parse_line] ssh_config_parse_line: Unapplicable option: SendEnv, line: 68
[1] [local_parse_file] local_parse_file: Cannot find file /etc/ssh/ssh_config.d/* to load
[1] [local_parse_file] local_parse_file: Cannot find file /etc/ssh/ssh.d/* to load
[2] [ssh_connect] ssh_connect: libssh 0.9.0 (c) 2003-2019 Aris Adamantiadis, Andreas Schneider and libssh contributors. Distributed under the LGPL, please refer to COPYING file for information about your rights, using threading (null)
[2] [ssh_socket_connect] ssh_socket_connect: Nonblocking connection socket: 6
[2] [ssh_connect] ssh_connect: Socket connecting, now waiting for the callbacks to work
[1] [local_parse_file] local_parse_file: Cannot find file ssh_config.d/* to load
[2] [ssh_config_parse_line] ssh_config_parse_line: Unapplicable option: ForwardX11Trusted, line: 63
[2] [ssh_config_parse_line] ssh_config_parse_line: Unapplicable option: SendEnv, line: 65
[2] [ssh_config_parse_line] ssh_config_parse_line: Unapplicable option: SendEnv, line: 66
[2] [ssh_config_parse_line] ssh_config_parse_line: Unapplicable option: SendEnv, line: 67
[2] [ssh_config_parse_line] ssh_config_parse_line: Unapplicable option: SendEnv, line: 68
[1] [local_parse_file] local_parse_file: Cannot find file /etc/ssh/ssh_config.d/* to load
[1] [local_parse_file] local_parse_file: Cannot find file /etc/ssh/ssh.d/* to load
[2] [ssh_connect] ssh_connect: libssh 0.9.0 (c) 2003-2019 Aris Adamantiadis, Andreas Schneider and libssh contributors. Distributed under the LGPL, please refer to COPYING file for information about your rights, using threading (null)
[2] [ssh_socket_connect] ssh_socket_connect: Nonblocking connection socket: 8
[2] [ssh_connect] ssh_connect: Socket connecting, now waiting for the callbacks to work
[1] [socket_callback_connected] socket_callback_connected: Socket connection callback: 1 (0)
[1] [ssh_socket_exception_callback] ssh_socket_exception_callback: Socket exception callback: 1 (0)
[1] [ssh_socket_exception_callback] ssh_socket_exception_callback: Socket error: disconnected
SSH client killed (24.118.90.163)
[1] [socket_callback_connected] socket_callback_connected: Socket connection callback: 1 (0)
[1] [ssh_socket_exception_callback] ssh_socket_exception_callback: Socket exception callback: 1 (0)
[1] [ssh_socket_exception_callback] ssh_socket_exception_callback: Socket error: disconnected
Error connecting: Socket error: disconnected
SSH client killed (31.165.117.81)

[alnhk]

@nviennot : Please expedite.

[repomaa]

Having the same issue. The server shows:
fatal: Cannot create new namespace

[mehdihz]

Having the same issue. The server shows:
fatal: Cannot create new namespace

This happened because of SYS_ADMIN capability missing. Run docker with the below config to fix the issue:
docker run --cap-add SYS_ADMIN -v /etc/tmate/keys:/etc/tmate/keys -e SSH_KEYS_PATH='/etc/tmate/keys' -p 2200:2200 -d tmate/tmate-ssh-server