In this article we will look at the partition layout of ESXi 5.0. A change from earlier ESXi 4.x is that the older MBR partitioning system is replaced with a GPT style partition table. The first five partitions are mandatory and consumes exactly 900 MB together, while the last two is not technically necessary.

ESXi 5.0 partitions

The first small partition is just for booting the system and locating the hypervisor image which could be on one of the next two partitions.

The actual system image is located on the first 250 MB partition, formatted with plain old FAT. The image itself, s.v00, is a 124 MB compressed file, which is decompressed on boot and contains the hypervisor operating system.

The next 250 MB FAT partition is used for inplace upgrades and is empty at start if a clean installation was done.
 

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