1. Shared Access

• How much utilization are you expecting from your SAN?
• How many servers will share this storage?
• What are the I/O requirements necessary to support all of your hosts?

2. High Reliability and Availability

• How will your disks be protected?
• Do you know how different RAID types will affect performance?
• What happens if your SAN technology is outdated?
• Can you remove and add new technology without affecting downtime?
• How do you plan on protecting your very important data in your SAN?
Standard backup methodologies just are not enough anymore. You must consider functionality such as snapshots and replication.

3. Data Protection

• If your SAN fails for any reason, how will you restore this data?
• Have you established priorities to recover your mission critical applications?
• What if you could automate this?

4. Ease of Use

• This is one of the most important things to consider when weighing your purchase decision.
• How complicated is your SAN technology to manage?
• Do you need specialized skills and dedicated staff to manage your SAN?
• As you add more storage are you getting ALL of the benefits of the new drives from a performance perspective?

5. Cost Effectiveness

• How much does it cost?
• How much will all of those other features cost you?
• When comparing technologies with different features, how can you make sure you’re comparing apples to apples?

Selecting a SAN
Once you have taken into consideration these five main topics, you’re ready to select your next SAN. But with all of the different vendors in this industry how do you tell them apart? How will they work in your environment? How will they support you?

Traditional Storage Implementations
With traditional storage implementations, objects are bound to physical resources, statically configured, and operate as individual islands of storage within the SAN. In addition, performance and capacity resources are not easily reallocated and can be difficult to operate. Plus, professional services are often required to create the initial configuration and to make changes. With traditional storage implementations, every feature is an add-on cost and licensing can be expensive.

iSCSI?
Technologies such as iSCSI from vendors such as Dell EqualLogic can help make your storage
buying decision easy. I know you keep hearing things like iSCSI is just not fast enough to support the required I/O or that iSCSI is for Tier 2 storage. But consider this: 2GB Fibre Channel delivers 196MB per second. One 1Gb IP delivers 116MB per second but when teamed, it delivers 232MB per second…Interesting isn’t it? It’s not about the transport layer. It’s always about the disk infrastructure to support your I/O needs.

What You Should Expect from Your Storage Vendor:
             Block storage virtualization
                  - Abstracting the logical view from the actual physical drives
             Non-Disruptive growth
                  - Add capacity anytime
                  - Transparent to servers
                  - No downtime
             High Performance
                  - Linear scaling
                  - Grid capability
             Self Managing
                  - Rebalances as it grows
                  - Tunes automatically in response to workload
             All inclusive Enterprise features
                  - Fully redundant enterprise architecture
                  - Full integrated suite of features – NO ADDITIONAL COST

A Look at GreenPages’ Virtual Server and SAN environment
GreenPages faces the same challenges that our customers do when it comes to making the best decisions to support our business. After we considered all of the questions above, we ended up choosing a Dell EqualLogic SAN for our large virtual infrastructure.

Diagram of GreenPages’ Infrastructure

VMware Site Recovery Manager
In order to take complete advantage of the SAN features relative to Disaster Recovery, we deployed Site Recovery Manager (SRM) for our virtual infrastructure. SRM manages and monitors recovery plans and is tightly integrated with Virtual Center. Using Dell EqualLogic’s iSCSI SAN storage adapter allows us to coordinate with Virtual Center to leverage array replication for testing and failover.

Leveraging Virtual Desktop Infrastructure
When it comes to VDI deployments, one of the more consistent bottlenecks continues to be the disk I/O. During the boot process of virtual desktops, the disk array needs to be able to handle all I/O requests and sustain performance for the remainder of the activity, which makes block virtualization better technology to implement when dealing with performance requirements.

In Conclusion
When combined to support server virtualization technologies, businesses need to understand the impact of how misconfigured or unplanned storage impacts the ability to deploy and even scale out server virtual environments. For a deeper dive into specific strategies that will help you evolve your virtualization strategy, check out our most recent webinar, "Demystifying Storage and Virtualization."