shutdown Graceful shutdown. Indicates shutdown [options] -h halt the system when shutdown 5 –h how long to wait before shutting [when] shutdown is complete (shutdown in 5 minutes, down and whether to reboot or -r reboot the system when halt after shutdown) halt afterwards. shutdown is complete shutdown now –r (reboot now) useradd Create new user (must be root) useradd [options] -D view defaults useradd sales –g –c [user] (/etc/login.defs & lastname” “firstname /etc/default/useradd) userid -g specify group -c name comment Command Explanation Format Options Example userdel Delete user’s account permanently userdel [options] -r remove home directory userdel userid –r [user] and files groupadd Add a new group account groupadd [options] -g group ID (GID) groupadd 919 –g managers group groupdel Remove group from account files groupdel None groupdel managers top Information about CPU-most top [options] -c show command line top intensive processes currently -s secure mode r running (frequently refreshed 5 r apply renice (priority) to 1066 (PID) – seconds) a process (negative = 10 (new important, positive big = NI column changed to less important) 10, process moves down q quit in the list free View statistics about memory free [options] -t display totals free usage (RAM and swap), buffers used by the kernel uptime Current time, amount of time uptime None uptime logged in, number of users logged in, system load averages
shutdown Graceful shutdown. Indicates how long to wait before shutting down and whether to reboot or halt afterwards. shutdown [options] [when] -h halt the system when shutdown is complete -r reboot the system when shutdown is complete shutdown –h 5 (shutdown in 5 minutes, halt after shutdown) shutdown –r now (reboot now) useradd Create new user (must be root) useradd [options] [user] -D view defaults (/etc/login.defs & /etc/default/useradd) -g specify group -c name comment useradd –g sales –c “firstname lastname” userid Command Explanation Format Options Example userdel Delete user’s account permanently userdel [options] [user] -r remove home directory and files userdel –r userid groupadd Add a new group account groupadd [options] group -g group ID (GID) groupadd –g 919 managers groupdel Remove group from account files groupdel None groupdel managers top Information about CPU-most intensive processes currently running (frequently refreshed – 5 seconds) top [options] -c show command line -s secure mode r apply renice (priority) to a process (negative = important, positive big = less important) q quit top r 1066 (PID) 10 (new NI column changed to 10, process moves down in the list free View statistics about memory usage (RAM and swap), buffers used by the kernel free [options] -t display totals free uptime Current time, amount of time logged in, number of users logged in, system load averages uptime None uptime
Commands_changed.docx