How did partition 7 get created?
It looks like the core dump partition which is usually last in the table.
partiton 4 is the extent
This does not look correct to me.
It should look more like this.
Device Boot Start End Blocks Id System
/dev/sda1 * 1 13 104391 83 Linux
/dev/sda2 14 650 5116702+ 83 Linux
/dev/sda3 651 17513 135452047+ fb Unknown - This is the vmfs partition
/dev/sda4 17514 17849 2698920 f Win95 Ext'd (LBA)
/dev/sda5 17514 17582 554211 82 Linux swap
/dev/sda6 17583 17836 2040223+ 83 Linux
/dev/sda7 17837 17849 104391 fc Unknown - This is the core dump partition
You need to reinstall ESX again and get it partitioned like this example.
Then I think you will have the results you were expecting.
http://blog.laspina.ca/
vExpert 2009