VM vs VHD(X) Location SSD VS Mechanical HDD

Discussion in 'SSDs & Data Storage' started by Clickinaway, Sep 16, 2013.

  1. Clickinaway

    Clickinaway n00b

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    Going to attempt to keep this as lean of a question as possible, but please ask for more relevant background info should you require.

    Slowly building a small server for a variety of purposes, but far from a production deployment. For now, as I said, I'll spare most of the specs. MOBO supports 2 SATA III channels. One of which is currently occupied by a small SSD drive which my Hyper-V Server 2012 hypervisor sits on (I know I could use USB flash drive but didn't have one that would mount as non-removable).
    I'd like to use the other SATA III connection for one more SSD, slightly larger for my Guest OS's, and then use a decent RAID controller for my 6 hotswap SATA drives (mechanical/platter drives to be determined; RAID configuration TBD as well, but may use 2 array's, may use one big array, all up in the air).
    One of the purposes of the server will be streaming music, likely with Plex. File system also TBD.
    There's so much material out there regarding location of VHD's (SSD vs HDD), but I cannot find much about the location of the actual VM's. In some cases, the data associated with the guest OS may be large (especially in the case of music) which leads me to believe that having the VHD's on the mechanical drives would be necessary (I guess also given that there isn't much in the way of redundancy for my proposed SSD VM location)

    I had wanted to also have a guest OS using FreeNAS but have recently become concerned about the intricacies of that in a virtualized environment.
    Focus for this is the location of the VHDX's vs VM's. Suggestions or pros & con's welcomed!
     
  2. Firebug24k

    Firebug24k [H]Lite

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    I store my ESXi boot and FreeNAS images on a thumb drive/SSD. Once those boot, and my storage is now accessible, I share out a directory from FreeNAS that holds my other VMs via NFS. It's pretty automatic without anything special from me - ESXi boots, FreeNAS boots, ESXi initially shows all my VMs as missing, but as soon as the NFS share comes up, it marks them as available again and everything boots up fine.

    VMs are on 4x SSDs in RAIDZ1.

    Alternatively, you can just store ALL your VM images on a single (or RAID1) SSD. Just don't store the data (music/whatever) on the VM image, store it on the NAS share. I'd not put them on the spinning platters HDs. If you go the route of ZFS or something similar, you can enable compression on the VM volume, which in my case nearly doubles the amount of free space at no performance loss (due to all the repetitive data in a bunch of similar VMs).

    I've been running this system for three years, and it's served me well with around 15x VMs on it right now. Even migrated from ESXI 4 to 5 and from Solaris to FreeNAS, the concept worked fine.
     
  3. westrock2000

    westrock2000 [H]ardForum Junkie

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    For what it's worth, having music on an SSD is wonderful, because the streaming device never has a pause. Whether it's when you first start playing music (platters spinning up) or going to random songs (no seek time).

    On a whim I moved my music over to a dedicated SSD several years ago, and the difference was subtle but noticeable. Since then I have kept my music exclusively on an SSD.

    But let me be clear, it's not a "hassle" or anything to be on platter. It's just one of the subtle differences you notice in just about any situation an SSD is used.
     
  4. Clickinaway

    Clickinaway n00b

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    Thanks guys for the really great info specific to the streaming side of things. Regarding that, I've read several articles about not virtualizing FreeNAS. I really like the idea of my server supporting a NAS share, but will likely have to opt for NFS. I haven't decided on the OS i'll use for Plex yet.
    Bear in mind that I will also be standing up a RDBMS (smallish), so the final mechanical array has YTBD [I may run 2 drives in RAID 1 and 4 other drives in RAID 6 or 10, but this is for another thread!].

    I guess one thing i'm still looking to understand is best practices regarding VHD vs your VM image location? Intuitively, it seems to make sense that that the VHD would go on my platter array given the deeper storage.

    I was lucky enough to stumble upon the Norco 5.25" bay to 4x2.5" bay adapter to optimize that dumb bay on my server case, so it affords me a few SSD options...budget affords me only one other SSD purchase, so that's why I wanted to know about it being the best place for your VM image (or not) so I can provision space accordingly. I don't anticipate more than 4 guest OS if you include FreeNAS (which I still cannot determine if its a viable option, but my system does allow for pass through).
     
  5. Clickinaway

    Clickinaway n00b

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  6. vegaman

    vegaman n00b

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    Installing FreeNAS in a VM is a viable option, but it's easy to do it wrong which is why you'll find warnings against it.
    The usual way to do it is to pass through an HBA (like the IBM M1015) so FreeNAS has full control over the disks attached to it.
    The wrong way is using RDM.
     
  7. Clickinaway

    Clickinaway n00b

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    Vegaman, well thanks for that input, it definitely answers a future question I had.

    What I'm still looking for are general best practices in regards to the title of this thread.

    Maybe I need to remove the background detail from my initial post?
     
  8. Phog

    Phog Limp Gawd

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    I suggest two servers, one for your VM's, one for your storage.
     
  9. Clickinaway

    Clickinaway n00b

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    Hmm...I'm only talking about a TB or two for music storage...only 600GB ATM. rest of array to be uses for RDBMS & GIS.

    I don't have nearly the deep storage needs most of you have on here or on STH. That's what all my gear at work is for!