Sam's San Diary #4: A Change of Heart

1. Too many servers to manage it on -- with about 30 servers in our data center, we would need to replicate another 30 servers in our disaster-recovery site.

2. With 60 servers, it also makes it very expensive for us [about $100K to license, $85K to install and configure and $2.5K per month for maintenance.

3. We have heard a few stories about failed attempts: A test install at our shop that failed, a failed installation by an uncertified reseller at another firm, and information from a third law firm that tried it for a critical legal application we also use and has yet to have any success.

Architecturally, NSI Double Take inserts a driver into my Windows I/O stack -- clever, but a bit worrisome.

My management has also spoken this week. We are to establish decision criteria in April, select by mid-May, deploy in production from June to September and in that same September timeframe begin replicating to a disaster-recovery site. Sounds reasonable, but there are some catches.

1. The only proven technology, EMC Symmetrix, is too expensive by a factor of three for our budget.

2. The EMC CLARiiON lacks the configuration flexibility we desire, and the replication strategy offered has a name that hints at its low appeal -- Fractured Logs. However, the company is talking future software products for each of these concerns.

3. The HP EVA lacks a shipping replication product. HP has one it is porting from another platform and claims it is in late beta. But I have letters from resellers last year (and have seen old press articles) that say it should have shipped already. Is it really a port or a new (and better) product? Is disaster recovery the business need where you take a chance? Will a good testing plan and a contract with clear deliverables provide a reliable solution?

4. If I suggest we look at other storage array vendors like IBM or others, the technical analyst I am partnering with on this project will hit the roof. And since these two do dominate the marketplace, I doubt I'll find greener grass anywhere else.

But wait, there is another approach to consider. We could look at SAN-based replication. Switch-based products are just being developed, but external appliance products exist. And I think one of them (FalconStor) is in use at another law firm, something that is important to us because we law firms tend to have a herd mentality. Also, HP has a product called CASA -- formerly known as the SV3000. This might result in a more expensive and more complex solution that we want, but at least the products exist today.

NEXT WEEK: Sam figures out specs for his SAN.

Sam Blumenstyk is the technology operations manager at Schulte Roth & Zabel, a midsize Manhattan law firm. Each week, follow Blumenstyk along as he upgrades his company's storage infrastructure and builds a SAN.