I am going from MBR disks to GPT disks and I am having problems online enlarging the GPT disk. I do not use LVM. I had a way of doing that online with MBR but with GPT he complains about the backup GPT table not being at the end of the disk. Can someone give me a clue on how to properly online enlarge a GPT disk/partition? Partition on it is EXT4 at the moment. I can get it to work when parted fixes the problem but I want to script it and that seems not possible at this moment.
Hi and welcome to the Forum 
You would need to look at sgdisk, partprobe and resize2fs…
For sgdisk the -e option would move the second header to the end of the disk, then recreate your partition and resize as required.
Perhaps some details of the disk/partitions in question?
This is a test system to try on, not a production one?
The disk is a regular disk in vmware. It is on a test system because I am still searching for the right procedure. It is a datadisk mounted at a non default directory. Ext4 is the filesystem.
I actually have a procedure for MBR disks and wanted to make the same for GPT disks.
- vmware enlarge disk
- rescan disk : echo 1 > /sys/block/sdX/device/rescan
- fdisk : delete then new partition
- reread partition table: partx - u /sdX
- enlarge filesystem : resize2fs /dev/sdX1
The first two steps are working fine. But for the third step I wanted to use gdisk. And there it failed (the partition I could make was exactly the same as before, so not bigger). Then I used parted and it told me to fix the disk because the backup GPT table was not at the end of the disk. After parted fixed it, I went back to gdisk and did the same as in fdisk for MBR.
After that I tried partprobe but that didnt work (said the system was still busy, it was mounted) but partx worked. As did resize2fs.
So I actually managed to do the online enlarge but I cannot script this way. It is kind of a big detour which I want to avoid.
I will have a look at sgdisk. Thank you.