If you want to do this via the classic ESX Service Console, you can take a look into vimsh for your snapshot operation:
[root@himalaya ~]# vmware-vim-cmd vmsvc/snapshot.remove
Insufficient arguments.
Usage: snapshot.remove vmid [removeChildren] [snapshotLevel] [snapshotIndex]
Remove a snapshot on the vm.
I forget offhand which way the index level grows, you may want to do some testing but I think you just need to modify the last param snapshotIndex and it'll either start 0 and grow or the opposite value.
A more elegant solution is to use the vSphere SDK/VI SDK which allows you to just remove a particular snapshot by name RemoveSnapshot_Task() http://www.vmware.com/support/developer/vc-sdk/visdk400pubs/ReferenceGuide/vim.vm.Snapshot.html#remo... but this will require you to run a script outside of the ESX Service Console on either a Windows/Linux or on vMA
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William Lam
VMware vExpert 2009
VMware ESX/ESXi scripts and resources at:
VMware Code Central - Scripts/Sample code for Developers and Administrators
VMware Developer Comuunity
Twitter: @lamw
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