1) How to add user in linux.
The syntax is as follows:
# adduser username
# useradd username
2) How to delete user in linux.
#userdel username
3) How to set password for a user in linux.
#passwd username
4) How to lock user account in Linux.
The syntax is as follows:
#passwd -l {username}
5) How to unlock user account in Linux.
#passwd -u {username}
6) How to create group in linux.
The syntax is as follows:
# groupadd group name
7)How to add user to group
.
# useradd -G group name username
# useradd -G group name username
8) What is UID for root user.
# id root
uid=0(root) gid=0(root) groups=0(root)
9) How to check os version in linux.
# cat /etc/redhat-release
#cat /proc/version
#cat /proc/version
10) How to check free disk space in linux.
#df -h