Setting up openssh-server (1:7.2p2-4ubuntu2.1) ...
Creating SSH2 RSA key; this may take some time ...
2048 SHA256:98ONRH/YVE1YPZXLZhT5Z9fChL53mOp6YvItMWkQ45o root@surendra-Vostro-1540 (RSA)
Creating SSH2 DSA key; this may take some time ...
1024 SHA256:oDGGUWnfPR9vSlBpv9iGW0rNt6O4Wi2MyNtr8UuDpE4 root@surendra-Vostro-1540 (DSA)
Creating SSH2 ECDSA key; this may take some time ...
256 SHA256:dbNroDlYygcS7RP67wQXTEEFnDDwnFcHiOa48tbKx3g root@surendra-Vostro-1540 (ECDSA)
Creating SSH2 ED25519 key; this may take some time ...
256 SHA256:jcZcAoYAv8v8T/JvGcvo+zx4WJo5DBL6WkekEOxCBtk root@surendra-Vostro-1540 (ED25519)
Job for ssh.service failed because the control process exited with error code. See "systemctl status ssh.service" and "journalctl -xe" for details.
invoke-rc.d: initscript ssh, action "start" failed.
dpkg: error processing package openssh-server (--configure):
 subprocess installed post-installation script returned error exit status 1