Businesses often develop their IT infrastructure as they grow, which means that applications are sometimes deployed on an ad hoc basis. This can cause database sprawl, a situation in which a company operates multiple database servers, each for just one application. Database sprawl costs money in hardware, software licenses and maintenance, and the performance of some applications may suffer. If your client has more than a few database servers, database consolidation services may be good for them -- and for you.
Database sprawl results when a company creates new database servers for applications at deployment, rather than setting those applications up to use an existing database. Database sprawl is most common with Microsoft SQL Server, according to Hilary Cotter, a SQL Server consultant who was awarded Microsoft's Most Valued Professional (MVP) status in 2001. Compared with Oracle Database, for example, SQL Server is cheap and easy to install, so departments within a company are more likely to set up their own servers without consulting IT. Many applications are also built on SQL Server Express, a free edition of SQL Server that is often either embedded or included with those applications.
The same conditions that created the sprawl often lead to a server being treated as "just a magic black box that works," said SQL Server consultant and MVP Geoff Hiten. Those machines may be unpatched or unreliable, and restoring them after a disaster or server failure can be difficult if nobody knows exactly what's on them.
Benefits of database consolidation
SQL Server database consolidation can save your clients substantial license fees, since they won't need to maintain as many instances of SQL Server. One consolidated server is also easier to maintain than several sprawled servers, so your client's maintenance and tech support costs will go down.
"Managing one server for one function is simple. Managing 20 servers for 20 functions is complex. Managing one server for 20 functions is somewhere in between," Hiten said.
Customers can also lower their risk of server failure with database consolidation, since it will mean they have fewer computers -- and thus a lower chance that any one of them will fail, Hiten said. On the other hand, those consolidated servers will need to be more reliable, since each one will be more important.
Database consolidation gives you a good opportunity to look at your client's servers, document them and make sure they fit into a regular maintenance program. With fewer physical servers to worry about, patches and upgrades become more manageable for IT, Cotter said.
Database consolidation can also make it easier to comply with regulations such as HIPAA that require companies to restrict access to certain information. One consequence of database sprawl is that information tends to be duplicated in several servers. While that can be a problem in itself, it makes it particularly challenging to ensure -- and prove -- that any server that may have sensitive data is secure. By consolidating databases, that chore becomes simpler.
Likely candidates for database consolidation
It's hard to predict whether a company will suffer from database server sprawl based on its size, Hiten said. Some companies may have many employees but a relatively simple IT organization, whereas others -- particularly high-tech, Web-based companies -- may have relatively few employees but a complex IT infrastructure that has grown organically and could benefit from database consolidation.
One good indicator of sprawl is that a company is supporting multiple versions of SQL Server, Hiten said. That can point to a silo-style development history, in which new applications are deployed independently and not integrated into the existing infrastructure.
Another sign of sprawl is when some systems are more reliable than others -- and the best-performing servers aren't always the most crucial, Hiten said. Those inconsistencies come from the same problems that may lead to server sprawl: a disorganized, unplanned IT infrastructure.
But even if your client's infrastructure is suffering from SQL Server sprawl, database consolidation may not always be appropriate, said Bill Graziano, a partner with ClearData Consulting Inc., a Lenexa, Kan., consultancy for SQL Server.
Because each consolidated server will have to do the work of several servers, its hardware needs to be much more robust. For instance, if your client will need to replace its low-end disk array with a high-end SAN to deal with the increased I/O load, the project could get prohibitively expensive, Graziano said. In the next installment of our Database Consolidation Services Hot Spot Tutorial, we'll take a look at how to plan a database consolidation -- and give advice for determining when it's best to just leave a server as it is.