How easy is it for you to convince management to spend $11,500. Or how about $26,600 or even $47,000? Those are the numbers I found when I began looking for a SAN solution. Yeah sticker shock, for me. Heart attack for the executives. When you’re an SMB and a solution costs upwards of $50k or more, people are going to baulk.
My environment was quickly running out of disk space. Running VMware vSphere, the overhead of RAID and thick provisioning of VMs began limiting my disk space. My options were buy more physical servers or get a SAN.
I knew I was going to run out of space again if I bought more physical servers. Disk space was my top concern. Running VMware vSphere, you pay a license per processor. On top of that, I had to increase my license for Veeam. Those costs are nominal in comparison to purchasing a SAN. So how else could a SAN be justified? How could I translate the benefits of moving to a SAN in plain English. How can the organization save in the short term or long term by purchasing a SAN?
Large Capital Expense
SANs are not cheap. Even if you could get a SAN on the cheap my concern was it lacked all the features we need out of a SAN. Having more storage is good and when moving to centralized storage – all your data is in one big basket. When the SAN craps out and all data is inaccessible then that’s another expense on top of the SAN (and whole other discussion.) Whether that’s lost sales, lost productivity due to an outage in your virtual environment, or you *gasp* lost your data completely.
It’s not just a big dollar expense. It’s much more than that. It’s now the mission critical system in your environment.
What Are The Business Requirements
We needed redundancy and high availability. With our current VMware vSphere license we were unable to utilize features such as vMotion, High Availability, and Fault Tolerance. We grew out of the base ESXi install. We had no shared storage. All virtual machines were stored on local disks on each server. Moving them required downtime. I couldn’t move them anyways because of the lack of storage on other hosts.
Can you imagine how I could lose sleep over this?
The SAN itself can be made redundant through dual controllers, dual network interface cards, and RAID. For high availability you can enable features for automatic failover in the case of hardware failures and you have MPIO.
Maintenance is improved with the ability to failover hosts, both within a SAN when updating a controller’s firmware and also when updating VMware hosts – just vMotion the virtual machines to another host.
Minimize downtime by restoring from snapshots or by taking advantage of VMware’s HA and FT.
The summary bulleted list of the business requirements:
- Minimized to zero downtime
- High availability
- Faster recovery time
- Performance increase
What Benefits Am I Receiving?
Most of the benefits realized with a SAN are not seen by upper management. If we could consolidate our storage into a centralized system with built-in redundancy and high availability, that would free up my administration time to other projects.
Centralizing the storage would be the greatest benefit. Instead of managing individual storage pools on each physical server I am now managing one. In addition, the SAN enables us to build out a highly redundant environment.
A short bullet list of the benefits with incorporating a SAN:
- Recovery time decreased when using snapshots
- Reduced power requirements due to limited purchase of additional servers
- Simplified Microsoft licensing – purchase of Microsoft Server Data Center Edition
- Simplified management of infrastructure – less physical servers
- Disaster recovery testing is automated as a result of increased storage (through Veeam)
- Eliminates single point of failures
- Increased redundancy using multiple paths to shared storage
- Utilize High Availability and Fault Tolerance with VMware
- Removes storage limitation per physical server
- Better disk utilization
Although favorable outcomes are achieved with deploying a SAN there are some unfavorable consequences as well. A SAN requires the expertise of storage area networking. Do you have the skillset to manage a SAN? If you haven’t managed a SAN before, how do you expect to troubleshoot when things go south?
In addition to the cost of the SAN, think about purchasing professional services and a good support contract. The way I planned on using professional services was to plan the installation myself, test the unit and also install it myself (before placing into production) and have the professionals validate my installation.
What should be expected in a support contract? Being that this unit is holding all the data and virtual machines, I would opt for a highly responsive support system. That could mean getting support within 1-2 hours. Getting an engineer within 4 hours. Getting parts delivered to you within 4 hours. It will all depend on how long your company can afford to be down, or in management speak – how much money can we afford to lose?
How good will support be? That could mean sticking with the known vendors. Possibly Dell, EMC, or NetApp? If you go with a lesser known vendor but what kind of support will you receive? Will you take the risk of having community only support? Do you want a resume generating event? I don’t think so.
- Get educated
- Purchase the right support contract
- Pick your SAN vendor wisely
What Features Do I Need in a SAN?
One of the biggest decisions I had to make was to pick 1GbE or 10GbE. Only you know that answer. You must know what your utilization looks like. If you have lots of users and communication going between your hosts and storage then you probably need 10GbE. You’ll need to gather those performance metrics.
If you’re lucky you will have a SAN that does both 1 and 10GbE. The cost will be in the switching hardware.
This is where you really need to do your homework or must rely on the vendor you select, the storage protocol:
I opted for iSCSI, primarily for the low cost and simplicity. iSCSI is supported by VMware and has tested well in my lab. This is where I will mention the double-edged sword again. If you haven’t worked with a SAN before, there is a lot to learn. You can probably get away with deploying a SAN but the real question is: Was the SAN deployed properly?
There’s more to just buying the SAN. Here’s an example shopping list:
- VMware vSphere
- Switches – *Don’t forget the tranceivers! Look into the packet buffer as well.
- HBA cards
- Estimated cost: $70k+
The numbers are just an estimation. Software licensing will depend on how many processors are used for VMware and Veeam. Cost of the switch depends on your needs – I quoted lower end switches.
So which SAN did I end up deciding on? The NetApp FAS2240-2 HA. A dual-controller SAN in one chassis. $47,000 is not what I paid for. That was the price I found online.
SANs are expensive. Finalize what features you need before shopping for the SAN. Will you need deduplication, how much storage do you need, high availability, redundancy, etc. What kind of storage protocol will you be using? Educate yourself on SAN technology. Understand the proper configuration for your environment needed such as disk utilization, high availability configuration, and troubleshooting. There’s so much more..
If the cost is just too damn high then take a look at other options such as a NAS, direct-attached storage, or maybe a strategy with Veeam.