bajorgensen wrote:
The most important part is not to use thin on thin, you can get some nasty surprises then...
We use thick-eagerzero (as 3PAR has zero detect) and overprovision the heck on the 3PAR.
You just need to be monitoring carefully and order more shelfs early,
we've been in the high nighties and the storage guys biting nails while waiting for HP to get a free consultant to install.
Hi,
First thank you all for valuable responses - appreciate it!
@bajorgensen - what kind of "nasty suprises" you think of ?
So far I got few suprises during TPVV tests - for example difficulties with storage reclamation when running vSphere 5.1 - had datastore, which was empty from VMware end (it was used before, but all VMs were deleted and/or svMotioned), space was reclaimed (few iterative runs) using vmkfstools -y, but on 3PAR end - it was still 60% used...
Also, with TP on VMware end, when VM is deleted, svMotioned or snapshot is deleted - free space is immediately available - on 3PAR had to wait hours until compactcpg process reclaimed space and sometimes not all space was reclaimed (as in example above).
BTW. Would would you do if new shelf arriving from HP is dead on arrival and they don't have replacement on stock (I saw both cases in my live - fortunately not together, but small chances it can happen) ?
With TP on hypervisor end I think risks are lower, because out-of-space can happen for single datastore at time, impacting tens VMs or less (it is very unlikely that all VMs would consume free space in same ratio, causing more datastores to be fully filled at same time), not for whole array, possibly impacting hundreds/thousands of VMs.
What about idea to set up limits on CPGs - possibly limiting out-of-space impact to selected group of VMs (non-critical, test, dev, etc) (so very highly critical VMs run on CPGs without TPVVs, and non-critical ones running on CPGs with limits) ?
Cheers!