Free space in VMFS during migration

[egr]

HI all,

we'd like to migrate from ESX 4.0 to ESXi 4.1U1.

We wil do a fresh install and a frsh install of VCenter server.

Our storage is an older EMC AX4 iSCSI.

My problem is that we have one VMFS (1,5 TB) which has only 140MB free space.

I know that this is not enough but at the moment we cannot get more and the VM in there is running...

We do not use Vmotion.

Now my question:

When I reinstall one of our ESX servers to ESXi 4.1U1 and attach this new one to the VMFS does ESXi 4.1U1 do anything withing VMFS that will consume space so we could get into trouble?

So could it be the case that we have less than 140 MB in this VMFS when we start the VM on ESXi 4.1U1?

kind regards and thanks in advance

/egr

[DSTAVERT]

It shouldn't change but I don't know anyone would guarantee it won't. With only 140MB free (less than 1%) you could be in trouble for almost anything. The VM swap file changes slightly???? You are at risk.

[nkrishnan]

Hope your going to install ESXi on local hard drive. It doesnt effect VMFS on the storage. But you should find a way to increase the free space by remove snapshot or moving the VMs to other storages.

[admin]

I know it will not create any catastropic failure theoritically. But what happen if your SWAP file size changes, does not happen often though. You are at risk and it may happen that you end up paying for this risk.

So mitigating this risk should be your prime concern now. Commit snapshot if there. Delete or move ISO files if possible. Din't we learn that VMware recommends at least 15% buffer to keep as head room.

My $0.02 !