View System Informations

View Kernel information

uname -r

View File System information

df -h

df -i

View File System Attributes

blkid

View Memory information

free -m

cat /proc/meminfo

View CPU information

cat /proc/cpuinfo

View Load information

uptime

# output result mean:
# Col 1 : The current time
# Col 2 : how long the system has been running
# Col 3 : how many users are currently logged on
# Col 4-6 : the system load averages for the past 1, 5, and 15 minutes.

cat /proc/loadavg

View current device mount list information

cat /proc/mounts

View current system interrupt information

cat /proc/interrupts

View service name by port number

lsof -i :PORT

netstat -lntup | grep PORT