Cape Breton Technology Users Group

Most servers that have RAID controllers with Hot Swap bays will support both SAS and SATA drives.  First I’d like to say that if you are looking at a server, you should really consider one with hardware RAID and hot swap bays for the drives as a minimum requirement.  A properly configured RAID system will allow you to replace a faulty hard drive without powering down the server and without data loss, how much is downtime worth to you?

I’m going to assume you picked the right server and now the question is “Do I go with SATA or SAS drives?”

A SATA drive can connect to a SAS interface, a SAS drive cannot connect ot a SATA interface.  Most SATA drives are designed for the consumer market where cost is a big factor.  Most consumer drives are based on 8 hours per day usage with a 10-20%* workload. They are designed to run at half duplex (one data direction at a time) with an I/O per sector of 77*.  Enterprise based SATA drive improved on these specs by being design for more usage, higher workloads and can run at higher temperatures, and cost more.  SAS drives are designed to be enterprise drives where performance and reliability are much more important than price.  SAS drives are design to be running 24 hours a day with a much higher workload and to withstand higher temperatures. SAS drives use full duplex and have an I/O per sector of around 319*, 3 to 4 times faster than SATA.  If you ever pick up a SAS drive, one of the first things you’ll notice is that they are much heavier than the SATA counterpart.

I guess you can see where this is going.  From personal experience, SAS based RAID system out-perform SATA based RAID systems.

Joe Clarke

*Some of the numbers used above are from Intel.

I’m not much of a blogger, this is the first time I’ve actually check out the dashboard for this site.  This site has only been up for a little while and I know I really haven’t been promoting the site as much as I should, so I was surprised to see SPAM waiting for us.  Just shows you, there’s nowhere safe from spam in the connected world.

It’s almost as bad as a few years ago (ok, maybe more than just a few years) I was installing a new server.  I connected to the Internet through a dialup connection to update the anti-virus software, while waiting for the update to download, they got a virus (it was cleaned after the update and a reboot).  I remember thinking at the time what was the chance of getting a virus from a dialup connection as I saw the tell tale sign of the virus pop up on the screen, just imagine the look on my face.

I’ll chat more on viruses and such in later blog entries.

Joe Clarke