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14

Yes, there are performance implications for long-running snapshots. There are even greater implications for consolidating delta VMDKs back to the original disk file. This can cause unresponsiveness in your VM's operating system or other undesirable behavior. VMware has templating and cloning functionality built into vCenter. You need a $600 vSphere ...


6

According to the screenshot below, you have an "Unconfigured Disk"... This means that the drive needs to be configured on your HP Smart Array B120i RAID controller before it can be used by an operating system or VMware ESXi. You can perform this from the ESXi command line using the hpssacli command located in /opt/hp/hpssacli/bin/hpssacli on your ...


4

ewwhite's answer is correct, but just to expand a bit more or the performance penalty, consider the following scenario: You create a VM. A virtual read from the vmdk takes one physical disk read of the same size. Fairly straightforward. Now imagine you take a snapshot of the VM. Now, for every virtual read, you're going to incur 2 physical reads, one from ...


3

Don't focus on snapshots. It's clouding your judgment :) VMware has templating and cloning functionality built into vCenter. You need a $600 vSphere Essentials license to enable this. You can create a VM to your taste, then clone it to a template. That template can then be used to generate new virtual machines. This allows you to have a "clean state" but ...


2

You're looking for: clustered storage heads connected with a dual-path SAS topology. QuantaStor(Linux) and NexentaStor(Solaris) can do this. You can also roll-your-own with a clustering suite like RSF-1. But really, depending on the requirement, this just adds complexity with a tiny increase in availability. The likelihood of complete head node failure ...


2

Searching for "gpl vnxe download +site:emc.com" finds this clause in the release notes (ver 2.3.1, if that matters): Open Source Licenses GPL-licensed code is included herewith. If you would like a copy of any such GPL-licensed code, please send a written request to "EMC Legal, 176 South Street, Hopkinton, MA 01748, ATTN: Open Source Program ...


2

I think that the root of this question is that there are two fundamentally different methods of doing snapshots. A VMWare snapshot means that is halts writes to its primary disk and instead puts all writes into a separate snapshot disk. Reverting to this snapshot means discarding all the writes since it was taken (which causes very little overhead), ...


2

A JBOD (Just a Bunch Of Disks) is just that. It has no controller aside from what is necessary to provide power and data lanes to the disks. In a case of a more sophisticated JBOD, you will see a backplane and, depending on the technology used, maybe an expander. The controller needs to be placed on the host's side, it will be connected to the JBOD with ...


2

I know you can do the following in Linux LVM and can only assume that it may be possible on other OS's: Use the Volume Manager to set up your redundancy and data striping for reliability and performance. Simply use both disks as physical volumes for a LVM volume group and create a LVM logical volume with the correct redundancy and striping when setting ...


1

JBOD used generally means exactly what it says on the tin - just a bunch of disks. There's no raid, no disk consolidation, nothing. You'll see a whole bunch of separate devices down your controller. Intel's 'JBOD' unit needs a RAID adaptor if you want to do anything more clever. For example: ...


1

Yes ZFS snapshoting works well for that, with no performance penalty for adding them as you please. (also easy to replicate for backup, etc) However there isn't any coordination with vmware though so you do need to remove and re-add them to the inventory manually when you revert snapshots. Whether it is a particularly good solution for you depends very much ...


1

Apart from what is already mentioned, from a performance point of view xfs on MD base raid performs better than zfs on streaming media. I've used the exact same hardware for half a decade with xfs and about the same amount of time with zfs on my media server. On the Intel Atom 330 with xfs I never experience stuter, on zfs on complex scenes the same hardware ...



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