Hello all,
I am currently testing VMware 5.1
I have 3 hosts A, B and C in HA mode with 3 attached SCSI disks (1 per host), 3 attached SSD disks (1 per host) and a fiber channel datastore called datastore1 shared between A and B
I have 5 VMs (VM1, VM2 ...VM5) on the same datastore datastore1 which is 99% full (400 MB free space on a 200 GB disk space) and shared on the A and B hosts
I attempt to migrate (only host change) these VM on host B and I got an issue
--> I can migrate VM1, VM2 from A to B but when trying to migrate VM3 I got an error message "Insufficient disk space on datastore datastore1"
It seems that VMware use a part of datatsore datastore1 during migration probably as swap disk or to store temporary data
So my questions are :
1) Does anyone can explain what are the mechanisms used by VMware during the migrate function?
2) What is the minimum percentage of free space on datastore I have to keep left to perform successfully the migrate function?
Many thanks in advance for your relevant responses 
Dominique