- by Chad, "The Dream", Weaver.
Today I want to talk about server storage in a small to midsized company.
I have noticed that the storage space is wildly spread out with some servers utilizing almost all of its available space, and with no drive bays to expand have to be monitored closely to prevent the drives from filling up. While other servers are massively under used, yet have a large storage array or a very large amount of disk space unused. You may even use this device to store network shares and documents from all the different users. It seems like such a shame to have all that space go wasted from where it is truly needed. If you can afford it, SANs are the perfect option to centralize your storage so that the space can be spread out accordingly, and not waste that hard disk space. It used to be Fiber Channel, which came with its own expense, then came iSCSI that use Ethernet to handle the data transfers.
There is a simple option you use to create a simple iSCSI target on your existing underutilized servers to connect via an iSCSI initiator to from a server that needs the space. This tool is actually from Microsoft surprisingly, and can allow you to turn a 2003, 2008 server in to a basic SAN. The software you need to get started is the iSCSI target client software the current version is 3.3 and after a short install of this software you can get started creating your first iSCSI LUN and target in almost no time. I have set this up and I will admit that you do have to have a basic understanding of how all this works. It really does help but, as always, good old Google can help you get through it. I can even write up a walk through in the near future outlining how it is all done. For now we will skip all that and go to what this can do for you. You can now create a virtual drive, in this instance of SAN the disks are created are Microsoft’s .vhd files. Once you have completed that, you assign that drive to a LUN. A server desperately in need of space acts as a local hard drive using Microsoft’s iSCSI initiator software that is installed on Windows 7 and a server 2008 by default and is a quick install on XP and 2003 systems. You can connect to the new target and initialize the new disk space format and name it as you desire and get started using that space.
There are a couple limiting factors here as this is a software iSCSI SAN solution and isn’t as full featured as some hardware solutions. It also helps to have a faster than 100 base-t Ethernet connected to your server. But if you have Gigabit Ethernet on your servers and an appropriate switch performance it’s actually pretty decent. Over all I would say this is a great way to utilize the wasted hard disk space on your servers and or expand a server’s storage capacity with what you already have without spending a single dime. Especially if you are just looking for storage capacity, I wouldn’t host critical databases on it, but it is amazing what you can do when you are no longer limited to the storage directly attached to your servers anymore. Also, in a pinch, it can also be used in Hyper-V implementations; you can attach the drive to the host system and attach that to the guest, or boot the guest from the host system and then attach the target to the guest system directly ignoring the host operating system that way. From here the sky is the limit think about it.