Virtualizing Microsoft Exchange is gaining momentum in the marketplace, especially after the GA of Exchange Server 2013. According to a survey conducted by ESG, 56% of the organizations had already virtualized their production Microsoft Exchange environment, while 19% planning to do so in the near future. ESG also did a lab validation of virtualizing Exchange 2013 on Windows Server 2012 with Hyper-V, where they were able to support 48,000 mailboxes on 12 virtualized Exchange mailbox servers, all hosted on a single physical server.
What I’m going to show here is another example of Exchange 2013 virtualization with Hyper-V: hosting 66,700 mailboxes on a single physical server and a NetApp storage subsystem.
The physical server is a Fujitsu RX300S7 (2-socket, 12-core, Intel Xeon CPU E5-2630 @ 2.30GHz; and 128GB RAM), running Windows Server 2012 Dataceter Edition. The storage is a NetApp FAS storage system running Clustered Data ONTAP 8.2. They were connected via multiple 8Gbps FC links.
Eight Hyper-V VMs were created, where each VM was configured with 2 vCPUs and 8GB of RAM (see Figure 1).
Figure 1. 8 VMs on a Fujitsu RX300S7 server.
Jetstress 2013 was used to simulate the Exchange 2013 workload. The total number of mailboxes is 66,700. That translates to 8,340 mailboxes per VM. Below are the Jetstress parameters on a per-VM basis.
- IOPS/Mailbox: 0.06
- Mailbox size: 1.0GB
- Thread count (global): 12
- Test type: Performance
- Run background database maintenance: Yes
- Continue the test run despite encountering disk errors: No
- Number of databases: 6
- Number of copies per database: 2
Figure 2 shows a sample Jetstress report (header portion) from the VM, MBX11. The other 7 Jetstress reports are virtually identical.
Figure 2. The Jetstress report from MBX11.
Figure 3 summarizes the test results on the per-VM basis. Specifically, the achieved IOPS exceeds the target IOPS by 37%. The average database read latency is 10.49ms and, write latency, 1.57ms. Both latencies are far below the 20ms threshold.
Figure 3. The Jetstress test results on 8 VMs.
It is worth noting that the “10,000-mailbox per server” restriction still applies to Exchange Server 2013. Without virtualization, each physical server can have up to 10,000 active mailboxes. With virtualization, each VM can have up to 10,000 active mailboxes. In our example here, virtualizing Exchange improves the mailbox density by 6.67 times. Therefore, some obvious benefits of virtualizing Exchange are: server consolidation and higher resource utilization, smaller datacenter footprint, and lower TCO.
Thanks for reading.