Is Spanning VMDKs Using Windows Dynamic Disks a Good Idea?

I've had several folks ask me recently about how to support very large NTFS volumes on vSphere virtualized Windows servers.  The current limitation for a VMDK in vSphere 5.1 is 2TB minus 512B.  FWIW, a Hyper-V virtual disk in Windows Server 2012 can be up to 64TB.  Those asking the question want to support NTFS volumes greater than 2TB for a variety of purposes - Exchange databases, SQL databases, and file shares.  Windows (depending on the version and edition) can theoretically support NTFS volumes up to 256TB (depending on cluster size and assuming GPT), with files up to 256TB in size (see … [Read more...]

vCenter Database Stats Rollup Troubleshooting

VMware vCenter collects performance statistics, tasks and events for historical performance analysis and auditing.  The collection level and retention of performance statistics can be controlled through the vCenter GUI (see Administration | vCenter Server Settings | Statistics).   The level of statistics collection and retention periods can have a dramatic impact on your vCenter Server's performance if not carefully planned and monitored.  In particular, the vCenter database can grow quite large and the database server required to support the increase in statistics increases in size and … [Read more...]