Disk Space:
Linux has a strong built in utility called ‘df‘. The ‘df‘ command stand for “disk filesystem“, it is used to get full summary of available and used disk space usage of file system on Linux system as follows:
# df
The df command provides an option to display sizes in Human Readable formats by using ‘-h’ (prints the results in human readable format (e.g., 1K 2M 3G)).
# df -h
RAM:
You can use the following commands to find out actual RAM usage on server
/proc/meminfo
It gives us the detailed usage about memory on the server. This file is used by free and many other commnads to display the amount of free and used memory( physical and SWAP) on the server as well as the shared memory and buffer memory used by the kernal.
# less /proc/meminfo
Or
# cat /proc/meminfo
You can use free command, It provide human readable output to show you the total amount of free and used physical memory and SWAP memory on the server as well as buffers by the kernal,
# free -m
Or
# free -g
