Virtualization Users Speak: (Nearly) 20 Questions with Pete Davis of the Spring Independent School District
Virtualization Users Speak: (Nearly) 20 Questions with Pete Davis of the Spring Independent School District
By VSM News Staff published: Monday, September 13 2004
A series of common interview questions with people around the globe using virtualization in their data centers.
Spring Independent School District in Houston is one of the largest school districts in Texas, serving more than 26,000 students. Over 1,900 teachers report grades electronically to the central office on a daily basis. Managing this data flow and the implementation of the grading program posed a challenge, with 26 servers spread across 23 locations. Pete Davis, Assistant Network Engineer, suggested the District consolidate using virtualization.
VSM: Why did you decide to implement server virtualization?
PD: We were running an application for each site that required a dedicated low usage server running Windows. The server was a 266 with 96MB of memory. After completing our wide area fiber project, we began to bring all our Novell servers back to the central office but we had no space for 26 tower servers. Rather than buy 26 new rack mount servers or leave the Windows servers at each site, I suggested we try VMware.
VSM: How do you use VMware and virtual machines?
PD: On the first ESX server, we run a gradebook application on 28 VMs, one for each school (some sites have two gradebook servers). We are using the second ESX server to consolidate all the administrative-type Windows servers that pop-up: work-order database, File Maker Pro servers, low usage Web servers, etc.
VSM: How long have you been using VMware?
PD: We’ve used GSX for a little over two years. We started with six servers and consolidated to four, doubling the RAM to 2GB. We have used ESX for about three months.
VSM: What products do you use?
PD: VMware’s GSX and ESX.
VSM: Who did the deployment?
PD: I did the deployment. We started with three VMs for a pilot using summer school gradebooks. After the successful three month pilot, we built 26 VMs for use during the fall semester.
VSM: What was the deployment experience like? Any problems or issues?
PD: The deployment was hit or miss. We had great success at times and horrible setbacks at other times. There were two main issues. First, we couldn’t get the Novell client to run as the primary GINA; still can’t on the GSX but ESX works like a charm. Second, we had MAC address conflicts causing hit or miss problems.
We worked with the VMware support team to get the Novell client to work as the primary GINA, as we wanted to log in to Novell before the local MS. They gave the normal “Check the FAQ/Check our website” answer the first time or two. After trying all of those solutions, they gave us three or four additional things to try. To date, we have never gotten the Novell client to work on GSX.
The MAC address problem almost stopped the project permanently on two occasions. When we first had the problem, the VMware people gave a short “Look for a MAC address conflict” answer. They never explained why this might be a problem and their Web site didn’t do a good job of warning or explaining this issue. They have since made great strides to emphasize this solution.
After about three support incidents and several emails later, one of their higher-level support people sent me an absolutely awesome explanation of how they do the MAC address assignments. Once I read the document, I understood what I was looking for on the network and how to set up VMs so it didn’t happen again. Under normal circumstances, MAC address conflicts are nearly unheard of, but the VMs are clones.
Their tech support people said it was very, very unlikely for us to have a MAC address conflict. They explained they rarely saw the issue. I thought that was odd since we had six servers (three MACs) with conflicts out of the original 24 servers. I don’t think that is ‘rare’. I suspect it happens more than they will admit to clients. Since that time, VMware has spent more time and effort to emphasize the MAC address issue in their tech support area.
VSM: What parts of the organization use VMs?
PD: Only MIS is using it at this time.
VSM: Have you used any other virtualization applications?
PD: No.
VSM: How has server virtualization affected hardware purchases?
PD: The first six servers were old 933 MHz/1GHz boxes with 1GB of memory. We were in the process of getting rid of them. We were able to use them for VMware GSX servers. We added an additional processor and they work great for hosting four VMs each. Later, we added an additional 1GB of memory and reduced the number of physical servers to four, hosting 6-7 VMs each.
We recently decided to purchase two quad Xeon servers with four 73GB HDD and 12GB of memory to host up to 32 VMs each. Instead of buying additional servers for new projects that require low usage servers, we can make VMs on the ESX servers or use the old dual 933/1GHz servers with 2GB RAM.
VSM: How has server virtualization affected IT staff?
PD: We have fewer servers to manage in the physical sense. We can set up a new server in a matter of minutes depending on the needs of the new application. We have more space in our racks as well as fewer cables. Our power supply needs have also been reduced. We don’t need as many outlets and we have more outlets available on our UPS.
VSM: Do you use virtualization as part of a DR or business continuity strategy?
PD: No.
VSM: Do you use VirtualCenter or VMotion?
PD: No.
VSM: What other features would you like to see in VMware?
PD: None. We will be looking into the VirtualCenter product next year. We should have about 40 VMs running by that time.
