With PAM limits, restrict each member of the students group to two simultaneous logins and a hard process limit of 100.
Choose the correct /etc/security/limits.conf lines.
Which setting is appropriate?
In limits.conf, @GROUP selects a group, hard selects the hard limit, and maxlogins and nproc are the relevant items. PAM must load pam_limits.
Detailed explanation
students soft login 2
students soft process 100Incorrect. It uses the wrong group/type and item names.
@students hard nofile 2
@students hard memlock 100Incorrect. It limits open files and locked memory instead.
%students deny login 2
%students deny nproc 100Incorrect. It does not use the limits.conf domain/type format.
@students hard maxlogins 2
@students hard nproc 100Correct. It sets hard maxlogins and nproc limits for the group.
Try it yourself
An example you can run in a temporary verification environment.
printf '%s
' '@students hard maxlogins 2' '@students hard nproc 100'Expected result
@students hard maxlogins 2
@students hard nproc 100Key points
- @ selects a group
- maxlogins
- nproc
Notes
- Environment: pam_limits設定行の表示のみ
- Command output formatting can vary slightly by distribution or tool version.
- Run the example in a temporary directory or process when possible.
Foundation review
Read the scope first
Check whether the command acts on the current shell, a new process, an existing process, or a file.
Verify the observable result
Use the supplied command and compare the output with the expected result.