Consolidating with SAN: ensuring a SAN solution is the right solution. (SAN/NAS Backup).

It is no secret that storage area networking (SAN) is a fairly new technology that, in recent years, has exploded into the infrastructures of many companies, whether small or large. With 2003 barely upon us, we can expect that this year will reap record-high sales for vendors in the storage industry. Systems consolidation can and probably will save corporations hundreds of thousands and quite possibly millions of dollars if done correctly. If the implementation of your SAN is not done with attentive care, you may be wasting your valuable company resources whether they be human or capital. There are several challenges and decision points that must be diligently reviewed before making the decision to consolidate to a SAN.

Know What You Are Consolidating

It is important that you first assess exactly what you are consolidating. You may be consolidating services, servers, sites or a combination of the three. In any event, this critical decision point will impact the solution throughout the implementation and long into your operational years.

Each service, application or customer population will, in fact, use a SAN differently than the other. Like anything else, SANs are highly configurable and fine-tunable based on what you intend to use it for. For instance, if you are utilizing a SAN for purpose of consolidating your email environment you will most likely want to configure your SAN with a RAID-10 configuration and ensure you have lots of cache available due to the thousands of reads and writes you may incur every second. This implementation is not practical if you intend to use the SAN for customer file storage. In that case a RAID-5 implementation is probably the most desirable solution.

If your goal is to consolidate sites then you may want to look at what the throughput requirements would be and what the network links are in between you and the end user given that the user can only send/receive data as fast as the network link allows. Given a network link that may be 1.54Mbps (T1) and you have 500 users you may not need to introduce the added cost of a 2Gbps Fibre Channel SAN and may easily get by with a SCSI160 or SCSI320 solution that is not as fast as Fibre Channel and, in many cases, is far cheaper but will still yield the 1.54Mbps that could ever be demanded of the disks in your SAN.

Know Why You Are Consolidating

This is a major point that should be addressed long before a solution is put together for your SAN environment. A business should determine its reasons for needing the introduction of a SAN. Be sure to not jump on the bandwagon and get a SAN just because it is the latest and greatest. For example, your company may want to consolidate its email services down to a few sites, because it is supposing that maintenance costs will decrease since there are less email servers in the distributed environment. The fact is that, although this may be true, it will also most likely increase the cost of the network links as well as backup systems as a result of added network traffic or increased capacity in a hub location. Make sure you know exactly why you have made your decision to introduce a SAN and all of the implications of that decision.

Know Who Will Be Implementing and Supporting the Solution

Always try and utilize the same vendor for the implementation and support of your SAN. With the limited abilities of storage management software it is common to choose another vendor for the software, but always try and keep your hardware consistent. In your initial assessment of the vendor itself, take into consideration the availability of tools for management of the solution. Whatever you can get for free from the vendor is a huge value add when it comes time to manage the SAN in a production environment and you no longer need to pay for an additional tool from another vendor, which will increase complexity and drive added cost into the solution. With storage standards still being developed and revised, many vendors implement storage protocols differently within their product set and will most likely make their solution different from the next vendor. This will undoubtedly drive much complexity into your environment, not to mention compatibility and supportability issues between vendors as well. Surely you can understand how one vendor would say it is the other vendors' fault that a particular device is not working or a LUN fell of the face of the earth. If you can manage to eliminate that situation, you have avoided one of the most crucial mistakes possible when you are implementing your SAN. Regarding backup and restore, it is desirable to sustain consistency, but it becomes less crucial because they are in fact two separate solutions that interface with one another based on whatever standard you have chosen, be it Fibre Channel or SCSI.

Get to know the vendors' ability to support the SAN technology present within your SAN and ensure that they fully understand what your SAN is used for, who is using it and what the impact to the customer is when the SAN becomes unavailable or is in a critical status. This ensures that the vendor is aware of the criticality of each situation and services your SAN provides based on that information.

Know Where Your SAN Will Be implemented

Location, location, location. This is a key factor when deciding where to consolidate your service, server or site. Many factors affect this decision and should be evaluated on an individual basis. For example:

* Site-readiness costs for your new hub location

* Power installation

* Power-loss protection

* Air-conditioner unit installation/upgrade

* Support-staff procurement 

* Telecom connection costs

* Environmental factors for your chosen region(s)

* Natural-disaster vulnerability/probability

* Terrorist-related activities

Try and choose a data center location that is the most stable location for your company's valuable data. If the wrong decision is made due to neglecting any of the important points above, your company will most likely suffer as a result. Each of these issues are important and will, in the long run, decrease the value adds that the implementation of the SAN has introduced.

Know When to Say When

This is probably the most important takeaway. Given that the storage industry is still evolving its standards and is still quite limited in its storage-management capabilities, it is very important to know when you are expecting too much from your SAN and when it should be broken up into smaller SANlets or islands. Like all technologies, SANs have their limitations and can only handle so much traffic or so many devices. To further complicate the issue, storage resource management software is still not quite up to par when it comes to large-scale SAN implementations and has a hard time managing larger SANs. Gartner recommends hanging up the gloves on your SAN at around 300-500 ports and creating another SAN island in an effort to maintain efficient support processes and ease troubleshooting efforts when you are in a critical state.

On top of the inherent limitations of SAN technology you must always be considering the factors that are indirectly related to your SAN, such as the telecom costs, disaster recovery, backup/restore and facility costs. If it is the case that many of your customers are offsite and your SAN is a large implementation, it is highly probable that your network costs will be quite high and you may want to consider creating smaller SANs closer to the majority of the population that is using the SAN. Disaster recovery, for obvious reasons, is becoming more and more a concern for all companies that require that their data be highly available and accessible at all times. The cost of a disaster-recovery solution becomes more and more interesting as a SAN solution grows. Disaster-recovery solutions most often need highly scalable tape systems that come at a large additional expense. Even given the significance of the tape-system cost, it does not compare to what it will cost for all the tape drives and tapes themselves. Fr om a backup and recovery perspective, it is often easier and more cost effective to keep your environment broken down into manageable pieces. It is far easier and cheaper to manage hundreds of tape cartridges than thousands; I think we all agree to that. Finally, the facility costs are always increasing as you introduce more equipment into your facility. Whether the added expense is for more network connections or added air conditioning it may not be worth your resources when a SAN achieves a certain size. What that certain size is depends entirely on your organization, but there is a break point for your organization or solution provider to determine.

As the need for consolidated, centrally managed storage systems grow, it will be crucial that the questions outlined above are answered in great detail and justified every step of the way. Advanced storage systems are costly at this point since they are a fairly new infrastructure technology and hiding behind the scenes are many added expenses that are not advertised on your choice vendors web page boasting lower TCO and increased ROI. 35% of companies that have introduced storage-consolidation methodologies are using network-attached storage solutions, which are a smaller and more cost-effective way to meet your storage needs. SAN technology certainly has its place within infrastructures both small and large, but the what, why, who, where and when are all questions you and your company should be asking as soon as the idea of SAN is considered.

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Joe Morin is project manager for Xerox Connect and owner of Rochesteritc.com