/Var issues check :

ls -lh /var/log/* >> check for the log files which is consuming high size


 ls -hrSal /var/spool/mail/*  >> Check for the account usernames which is consuming high size (above 50 MB) then,

tail -2000 /var/spool/mail/username


ls -lh /var/spool/mqueue/*  >> check the recent email headers using the command :

tail -2000 /var/spool/mqueue/id

Semaphores

# ipcs -s
If you see a list of semaphores, Apache has not cleaned up after itself, and some semaphores are stuck. Clear them out with this command:

 for i in `ipcs -s | awk '/httpd/ {print $2}'`; do (ipcrm -s $i); done

Command to check the most recent resources usage in cpanel servers

/usr/local/cpanel/bin/dcpumonview

Log location : /var/log/dcpumon/

Command to get recent reboot logs

 grep -A 10 -B 30 syslogd /var/log/messages

Command to check memory usage in windows server

tasklist /fi "memusage gt 90000" | sort /R /+58