ESXi 5: Disable software iSCSI from CLI

I am having trouble with the management agents on my ESXi hosts, as they keep crashing/not responding..

I am suspecting my iSCSI storage, as it works a bit like the wind is blowing - and we have more or less migrated away from it.

So I am looking for a way to disable Software iSCSI from the CLI (I have SSH access to the hosts) to see if that helps.

I get this error when restarting the services:
Not all VMFS volumes were updated; the error encountered was 'Timeout'.
The VMs are still running, so the VMFS volumes it's talking about is the iSCSI ones - which are not in use right now.