Expanding Drive Space in VMware for Linux use

Question

I use Ubuntu Linux to develop applications, but usually have a Linux admin setup the final environment. I have a Linux box (via VMWare) that houses our application and Docker containers. That works and is great.

We need to now expand the main drive / volume to be over 10 TB. Originally, for some reason they made the original drive only 1 TB. Now we have to make it larger.

The server team (via VMware) added for disk space to the VM (500gb) and I was able via some tutorials able to get that 500gb added to the drive via fdisk.

Great!, now they added 10 TB of space to the server. I can see the space but when I use fdisk i get that it can't partition space larger than 2 TB.

I read online that I can use gdisk or something like that. My questions are:

1) How can I get this 10 TB of space added to the server? and

2) If I set up this partition using something other than fdisk, can i later expand my main drive with this space since it wasn't setup in fdisk?

Answer 1

The 2TB limit you're seeing comes from the (ancient, circa 1983) DOS MBR partition table format. You are limited to 2³² sectors, which with 512-byte sectors is where 2TiB comes from. fdisk often supports only DOS MBR.

The solution to this is to use a newer partition table format, GPT. gdisk is one of several tools that handle GPT tables, and it will attempt to convert on start up. The conversion is done in memory only until you hit w. This would often fail if you hadn't just expanded the disk, but you have so it should work (GPT requires some sectors at the end of the disk as well as beginning; DOS MBR did not need the end).

When you fire up gdisk, you should see something like this:

***************************************************************
Found invalid GPT and valid MBR; converting MBR to GPT format
in memory. THIS OPERATION IS POTENTIALLY DESTRUCTIVE! Exit by
typing 'q' if you don't want to convert your MBR partitions
to GPT format!
***************************************************************

and you can use the normal commands you should be familiar with from fdisk to manipulate the GPT partition table.

Obviously, you should have backups in place, at very minimum your server team should snapshot your VM.

Long-term, you ought to consider using non-partitioned devices where possible, maybe through LVM. Then extending them is much easier and generally an online operation (for example, if you gave an unpartitioned device to LVM, it'd be a simple pvresize /dev/whatever, which takes a fraction of a second and is done online).

Answer 2

1) How can I get this 10 TB of space added to the server?

gdisk is an Ubuntu tool which gives you the ability to expand your partition.

2) If I set up this partition using something other than fdisk, can I later expand my main drive with this space since it wasn't setup in fdisk?

As the Man said, Yes, You Can. The tool originally used does not restrict you from using other tools. You might consider use of LVM because it's easier to adjust your partitions as things change.