Question Locked out from Server (ssh)

[Gregor]

Hey. the nightly update brought me the following error:
Server Error
500
Plesk\Lock\Exception
Lock Manager error: '[LockManagerException] Can't open or create shared memory by shm.name: "/run/lock/lmlib/SharedLockManagerStorage0.2.4"; shm.start_size: "8388608"; error "No such file or directory"'.

When i tried to login via ssh i noticed that port 22 is closed:
PORT STATE SERVICE
22/tcp closed ssh

I do have the Plesk firewall installed but was not aware it is blocking ssh?

how can i disable the firewall and or open any port for ssh.

i do have access to the server via recovery mode (Ubuntu, Strato)

Thanks for your help.
EDIT:
found a solution for all STRATO Users:
Plesk is not accessible: Can't open or create shared memory by shm.name


SSH still not working tho

 

[Bitpalast]

The section "In case SSH connection to the server is not possible" does not help?

 

[Gregor]

The section "In case SSH connection to the server is not possible" does not help?

The Part:
mkdir /var/run/sshd && chmod 0755 /var/run/sshd && /etc/init.d/ssh restart

throws:

Die Aufgabe "mkdir /var/run/sshd && chmod 0755 /var/run/sshd && /etc/init.d/ssh restart" wurde in 0 Sekunden abgeschlossen, jedoch traten Fehler auf

mkdir: cannot create directory ‘/var/run/sshd’: File exists



I found this answer as well:
Plesk is not accessible: Can't open or create shared memory by shm.name

i will try it tonight.

 

[Bitpalast]

These are three commands in a chain:
mkdir /var/run/sshd
chmod 0755 /var/run/sshd
/etc/init.d/ssh restart

The first one will throw an error if the directory already exists. In that case, simply omit it.
The second one will always work if the directory exists. You can run it separately.
The third one restarts the SSH service.

So you could try
chmod 0755 /var/run/sshd && /etc/init.d/ssh restart
or simply run the commands separately one after another.