Storage

Microsoft has a new file system designed to increase data integrity, scalability and availability called the Resilient File System (ReFS). This file system has leveraged many of the NTFS file system goodies and expanded them to make it more scalable and prevent corruptions. ReFS was released with Server 2012 and at the moment is designed for use with file shares. It cannot be used as a boot volume at the present time, but this file system seems poised to replace NTFS down the road. ...

Microsoft Storage Spaces feature used to handle data redundancy, scalability and performance. Storage Spaces takes a set of Just a Bunch of Disks (JBOD) and pairs them together to allow for; either failures of a disk, gaining the performance of multiple spindles, or gaining the space of multiple disks. Traditionally this has all been handled by creating a Redundant Array of Independent Disks (RAID) group. Some examples of RAID would be: Striping (RAID 0) Mirroring (RAID 1) Parity (RAID 5 or 6) Storage Spaces create a similar type of RAID Group but then throw a virtual disk on top of them so that multiple types of stripes can be used on the same disks. For example, three physical disks can be put into a storage space. From there, three separate types of VDISKs can be created, Mirrored, Spanned and Parity can then be placed on the same set of disks with no issue. The diagram below shows an example. ...

I was fortunate enough to get to spend an hour with Dmitriy Sandler from Nimble Storage to see what all the fuss was about with their product and more specifically their Cache Accelerated Sequential Layout (CASL) File System. Hardware Overview Let’s cover some of the basics before we dive into CASL. The storage array comes fully loaded with all the bells and whistles, out of the box. All the software features are included with this iSCSI array and include items such as: ...

Hard drives are not the most fun thing to talk about, but it’s important to know some of the concepts when it comes to disk latency. Disk latency refers to the time delay between a request for data and the return of the data. It sounds like a simple thing, but this time can be critical to the performance of a system. We should be surprised that traditional hard disks work at all when we consider that head designed to read minute magnetic fields sits 3 nanometers off a platter is spinning between 5400RPM and 15,000 RPM. Amazing when you stop to think about it huh? ...

Solid State drives are much faster than their spinning disk predecessors, but can also have performance degradation due to how they interact with Operating Systems. Flash consists of blocks of data and those blocks are full of smaller items called pages. A typical SSD might have block sizes of 512KB and 4KB pages. There are 3 statuses that a healthy page could be in on a flash disk. Written to: Data from the OS has been written to the page. Unwritten to: The page is free and available to be written to by the Operation System. Invalid: The page has data in it, but is available to be overwritten by the Operating System. ...

If you’ve got a some hardware lying around for your lab, Windows Server 2012 may be a great solution for a home storage device. You can now do both block (iSCSI) and NAS (NFS) on the same server, as well as having an OS to install some management apps on it. In my lab, I use this management server to run Veeam for my backups, PRTG network monitor for bandwidth tracking, as well as using this server for both iSCSI targets and NFS mounts. ...

HP announced a new virtual storage appliance (VSA) recently at their annual HP Discover conference. This is a virtual appliance based on the StoreOnce line (formerly known as D2D) of hardware appliances that HP has sold for a long time. These appliances have the catalyst software which allows for deduplication of all your backup data, hence the term StoreOnce. These devices have allowed administrators to switch from the older tape based backups to a virtual tape library (VTL) or a NAS type backup solution. It has replication options in it which allow for deduplicated data to be migrated or copied without re-hydrating the backups and wasting valuable bandwidth. It also allows for federated backups and when matched with HP Data Protector 8 (also newly released) can throttle bandwidth during backup operations in order to prevent production slow downs. ...

I recently purchased a Synology DS411slim NAS device for my home lab in order to quiet down my rack and start using up less power. Obviously to accomplish this I would need to fill it up with Solid State drives which have the added benefit of a large number of IOPS :) I screwed my four 480GB OCZ SSD’s into the drive cages and slipped them into the chassis. Really my only con for this device was getting the drives into the chassis. I did have to do a bit of wiggling to get them seated correctly. ...

I’m often asked about how to provision virtual machine disks. This almost always comes down to, “Should I use thick or thin disks?” and then “Should I do thin provisioning on the array or on the hypervisor?” So here we go: Thin vs Thick Thin provisioning: Thin provisioned disks don’t allocate all of the space during the provisioning of the storage. Instead, they allocate the space on demand. This is a great way to get more bang for you buck out of your storage. Let’s take a closer look with an example. ...

If you’re an engineer and you’re trying to get more experience with a variety of different storage devices, you might find yourself in a bit of a pickle. Most customers settle one one or two storage vendors and that’s it. So if you work for one of these companies you can learn EMC or Netapp, etc. I highly doubt your company would be interested in purchases a few different types of storage devices so that you can learn them as they are quite expensive. ...