OCI- Unable to ssh to instance with error "[FAILED] Failed to start Login Service"

APPLIES TO:

Oracle Cloud Infrastructure

Linux OS

SYMPTOMS

Console history shows below error :

[FAILED] Failed to start Login Service. See 'systemctl status systemd-logind.service' for details.

CHANGES

Oracle Linux 7 patching was performed

CAUSE

The files /etc/passwd, shadow, group, gshadow files were empty. But there was a backup

$ ls -l pass* gshadow* group* shadow* 
---------- 1 0 0     0     Jun 10 12:38 passwd  
---------- 1 0 0 10562 May 27 22:00 passwd- 
---------- 1 0 0    0    Jun 10 12:38 shadow 

---------- 1 0 0 3842 May 27 14:42 shadow- 

 ---------- 1 0 0    0   Jun 10 12:38 group 
---------- 1 0 0 3140 May 27 22:00 group- 
---------- 1 0 0    0     Jun 10 12:38 gshadow 
---------- 1 0 0 2962 May 27 22:00 gshadow- 
 

SOLUTION

1) Boot the instance into maintenance mode following steps in document: To boot into maintenance mode

2) From the Bash shell, run the following command to load the SElinux policies to preserve the context of the files you are modifying: