Craftworking

My Datacenter Pt. 2

Now for the storage. I decided to build one and load Freenas software.

There are a couple of points of consideration on building a storage appliance. The first is the raid controller. Buy the best raid controller that you can afford. I went with LSI. It ran about $500 for the 8 port version. It is also a good idea to purchase the cache battery. The second is memory. Rule of thumb is 1Gb of RAM for each Tb of disk space.

The nice thing about building the storage array yourself is that it can be customized for your particular application. The one I built has 3 network ports. I am using one for management and the other two are configured as a LAG group. This gives me 2Gbs for data transfer.

There are a number of other options for a storage appliance out there. In the end you get what you pay for. For example QNAP is one of the finest NAS boxes I have ever used. It has just about every feature you could imagine and is very easy to set up and use. However they are expensive. The Freenas box I built was half the price of a comparable QNAP box.

Freenas of course is free and runs on a BSD version of linux. The OS is very small and can be run from a thumb drive. This is how I am running mine. The storage array is equipped with 6 3Tb disk drives configured as RAID 5. This comes out to be just under 15Tbs.

NAS vs SAN. Look at the difference as how you get you data. NAS is basically a shared file system on a virtual machine. So your datastore is running off of the same network as your virtual machines. A SAN runs off of a completely different network dedicated for storage and is presented as a disk to the VMware host and is separated from the virtual machines.

Freenas and any good storage appliance will support iSCSI. iSCSI is the basis for SAN. Its a little more involved in the set up than NAS but is well worth the effort.

For my choice in hypervisors, I chose VMware. VMware is the king of baremetal hypervisors. But is also extremely expensive. You'll fork out about $2000 per physical CPU to get it. But the features it has are well worth it.

Networing was fairly easy to setup. Make sure that a managed switch is used. I found that switches with 1Gb ethernet ports are expensive. However I found a Cisco SG300 at Frys for about $200. It has 20 1Gbs ports which will be plenty for a SOHO environment. Unless you are doing exotic networking, this unit will work fine.

Another thing I am looking into is open network switching. These switches run open source instead of proprietary software. This is much cheaper than simialar equipment from Cisco or Juniper. I will post an article about this subject later.

Now for the problems I encountered with my setup. Remember I mentioned the server earlier? Well it turns out that VMware does not support SUN hardware any longer. I'm stuck with VMware 5.1. When I bought it, the hardware was supported. Not any longer. To upgrade to VMware 5.5 or 6.0, I will have to rip and replace the server. Another issue that may come up, but hasn't yet is the fact that I am only running one server. Once you virtualize your data life, everything is dependent on your hardware. Even if you are running this for your home, the data is critical. Everything is on that one machine. It is best to run two servers in a cluster to avoid something bad happening. My problem is I don't want to invest in another SUN server that can't be upgraded. I could buy something else to get by but I will wait to upgrade to something a bit more current to keep up with hardware compatibility. Otherwise my set up is working like a charm.

One last note on virtualization. Wheter you are running something like Fusion or a full blown setup with VMware. Virtualization itself give you a lot of flexibility you can't get from standalone systems. For instance lets say you spin up a virtual machine and it gets messed up. All you have do is delete it and spin up a new virtual machine. With snapshots, you can take proactive measures. Take a snapshot. If your virtual machine dies, gets infected, or some other disaster. You can restore your machine in just a few seconds.

In total I have invested less than $5000 in hardware. Even though my setup is small, it is an enterpise level setup.