Resize root partition (or how to remove the default /home partition) on CentOS 7 online
This requires you to be able to ssh into the instance using the root user account and that no services be running as users out of /home on the target machine.
The examples are from a default installation with no customation-you NEED to know what you're working with for volumes/partitions to not horribly break things.
By default, CentOS 7 uses XFS for the file system and Logical Volume Manager (LVM), creating 3 partitions:
Step 1 - Copy /home Contents
To backup the contents of /home, do the following:
mkdir /temp cp -a /home /temp/
Once that is finished at your back at the prompt, you can proceed to step 2.
Step 2 - Unmount the /home directory
umount -fl /home
Step 3 - Note the size of the home LVM volume
We run the
lvs command to display the attributes of the LVM volumes
LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert home cl -wi-a----- 406.94g root cl -wi-ao---- 50.00g swap cl -wi-ao---- 7.81g
Step 4 - Remove the home LVM volume
Step 5 - Resize the root LVM volume
Based on the output of
lvs above, I can safely extend the root LVM by 406GiB.
lvextend -L+406G /dev/cl/root
Step 6 - Resize the root partition
Step 7 - Copy the /home contents back into the /home directory
cp -a /temp/home /
Step 8 - Remove the temporary location
rm -rf /temp
Step 9 - Remove the entry from /etc/fstab
Using your preferred text editor, ensure you open
/etc/fstab and remove the line for /dev/mapper/cl-home.
Step 10 - Don't miss this!
Run the following command to sync systemd up with the changes.
dracut --regenerate-all --force