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A user reports that a service fails to start with the error 'Permission denied'. The service runs under a non-root user. Which command should the administrator use to check if the service has the correct file permissions?
The error 'Permission denied' when starting a service under a non-root user often involves not just the file's own permissions but also the permissions of each directory in the path leading to the service binary. The `namei -l` command recursively lists the permissions of every c…Read full explanation
A Linux server is configured to allow SSH access for remote administration. The security team wants to limit SSH access to only users in the 'ssh-users' group. Which configuration should be added to /etc/ssh/sshd_config?
The AllowGroups directive in /etc/ssh/sshd_config restricts SSH logins to only those users who are members of the specified group. By setting 'AllowGroups ssh-users', only users belonging to the 'ssh-users' group will be permitted to authenticate via SSH, directly fulfilling the …Read full explanation
A Linux server is not accepting SSH connections. The administrator wants to troubleshoot the issue. Which THREE actions should be taken?
Option B is correct because /etc/ssh/sshd_config is the primary configuration file for the OpenSSH daemon, and syntax errors, invalid directives, or a misconfigured ListenAddress/Port will prevent sshd from starting or accepting connections. Option C is correct because if the ssh…Read full explanation
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