Cannot enable ssh service on Ubuntu 20.04

W Lewis

1/10/23, 4:29 AM

I am trying to remote connet my desktop(Ubuntu 20.04.2 LTS) via MacBook. But my request is rejected. So I check my ssh status on Ubuntu.

sightvanish@SVPC:~$ sudo systemctl status ssh
● ssh.service - OpenBSD Secure Shell server
     Loaded: loaded (/lib/systemd/system/ssh.service; disabled; vendor preset: enabled)
     Active: inactive (dead)
       Docs: man:sshd(8)
             man:sshd_config(5)

It shows ssh service is inactive. Then I try to enable it manually.

/etc/init.d/ssh start
Starting ssh (via systemctl): ssh.serviceJob for ssh.service failed because the control process exited with error code.
See "systemctl status ssh.service" and "journalctl -xe" for details.
 failed!

So I do what it says.

sightvanish@SVPC:~$ systemctl status ssh.service
● ssh.service - OpenBSD Secure Shell server
     Loaded: loaded (/lib/systemd/system/ssh.service; disabled; vendor preset: enabled)
     Active: failed (Result: exit-code) since Fri 2021-09-10 11:38:27 CST; 21min ago
       Docs: man:sshd(8)
             man:sshd_config(5)
    Process: 13329 ExecStartPre=/usr/sbin/sshd -t (code=exited, status=1/FAILURE)

9月 10 11:38:27 SVPC systemd[1]: ssh.service: Scheduled restart job, restart counter is at 5.
9月 10 11:38:27 SVPC systemd[1]: Stopped OpenBSD Secure Shell server.
9月 10 11:38:27 SVPC systemd[1]: ssh.service: Start request repeated too quickly.
9月 10 11:38:27 SVPC systemd[1]: ssh.service: Failed with result 'exit-code'.
9月 10 11:38:27 SVPC systemd[1]: Failed to start OpenBSD Secure Shell server.

Then I check it,

sightvanish@SVPC:~$ sshd -t
/etc/ssh/sshd_config line 5: Deprecated option ServerKeyBits
/etc/ssh/sshd_config line 7: Deprecated option KeyRegenerationInterval
/etc/ssh/sshd_config line 16: Deprecated option RhostsAuthentication
/etc/ssh/sshd_config line 17: Deprecated option RhostsRSAAuthentication
/etc/ssh/sshd_config line 18: Deprecated option RSAAuthentication
Unable to load host key: /etc/ssh/ssh_host_key
sshd: no hostkeys available -- exiting.

Well, I generate new key sudo ssh-keygen -A But I still cannot enable ssh service.

sightvanish@SVPC:/etc/ssh$ sudo service ssh start
Job for ssh.service failed because the control process exited with error code.
See "systemctl status ssh.service" and "journalctl -xe" for details.

I am really confused. Please help me!

613

0 + 0

server

ssh

networking

matigo

1/10/23, 4:47 AM

A couple of questions: (1) have you connected to this computer in the past over SSH? (2) have you verified that `ufw` is allowing the connection?

Wayne Vosberg

1/10/23, 6:03 AM

for `sshd -t`, try `sudo sshd -t`. Host keys in /etc/ssh should only be readable by root. Then try `sudo /usr/sbin/sshd -ddd` -- this will output a lot of debug messages.

Wayne Vosberg

1/10/23, 6:06 AM

could also try `sudo systemctl reset-failed sshd` , `sudo systemctl enable sshd` , `sudo systemctl start sshd`

raj

1/10/23, 8:06 AM

If all else fails, I guess that purging the `openssh-server` package (purging, to remove all configuration), then optionally removing `sshd_config` and all `ssh_host_*_key*` files from `/etc/ssh` (if they are left there) then reinstalling it (which should install the default config and generate new host keys from scratch) should help.

pa4080

1/10/23, 9:31 AM

Does this answer your question? [SSH Server stops working after reboot, caused by missing /var/run/sshd](https://askubuntu.com/questions/1109934/ssh-server-stops-working-after-reboot-caused-by-missing-var-run-sshd)

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: Cannot enable ssh service on Ubuntu 20.04

TH: ไม่สามารถเปิดใช้บริการ ssh บน Ubuntu 20.04

RO: Nu se poate activa serviciul ssh pe Ubuntu 20.04

RU: Не удается включить службу ssh в Ubuntu 20.04

VI: Không thể bật dịch vụ ssh trên Ubuntu 20.04

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