I'm reminded every morning when I get up that I'm getting slower -- creaking and popping -- as I make my way to the coffee machine. If only I aged as gracefully as Windows Server. You've seen the latest marketing -- Windows Server 2012 is faster, more reliable and more resilient. Before you disregard it as normal hype, make the effort to take a look, because it's true.
In a recent article I discussed how you can accelerate live migrations in Hyper-V with Server Message Block (SMB) 3.0. But, there's more to SMB 3 than improved live migrations. The world of storage and access is changing, and Microsoft has hit it out of the park with SMB 3.
To be technically accurate, Windows Server 2012 ships with SMB 3.0 and the new release of Windows Server 2012 R2 includes SMB 3.02. What does all this mean? Imagine using a network share to connect to your data, regardless if it's a SQL database or (for us virtualization folks) a virtual hard disk. Instead of using iSCSI or fiber to connect to a SAN, imagine connecting your virtual machines to a storage device of your choice all over a network share. You will still have the performance, reliability and failover that expensive SANs can provide, but it'll be over an easy-to-configure simple network share.
Wouldn't it be cool to be able to put that mission-critical VM storage on the expensive high-speed storage and the less critical stuff on lower-cost storage without the configuration mess and hardware requirements? Did I mention this is a simple network share? No fiber, no iSCSI, just a simple "NET USE" command away. I'm sure you're assuming the performance wouldn't be enough, that you can't get the IOPS, but you would be wrong.
This isn't just a cute Microsoft feature; SMB 3 deserves your attention. Other vendors are beginning to adopt it. NetApp, EMC, Samba and even Apple are looking to implement it. Here's why:
- SMB 3 is specifically designed for server applications (including VMs) to store their data on file shares. This allows VMs to store their virtual drives on lower-cost storage but still maintain the best performance received by that storage. In simple terms, you can put VMs running low-use applications in a cluster connecting to shared low-cost (albeit slower) storage over network shares without the expense of a SAN and without the complications of fiber or iSCSI.
- SMB uses RDMA (remote direct-memory access) for direct memory-to-memory access, requiring very limited CPU time. This means you can host more VMs and access more storage points without losing performance.
- SMB gains from multichannel -- or multiple network interface cards (NICs). If you have multiple NICs teamed for this, then you benefit from the aggregate performance of all of them.
- Multiple NIC support also gives SMB the chance to seamlessly fail over between NICs or in the case of other network issues. In other words, you get the power of throughput by teaming NICs and the resiliency of instant failover.
- SMB also offers total encryption of data, so you don't need to worry about the hacker with a protocol analyzer sniffing your confidential data.
There is more to SMB 3, but the key takeaway for server virtualization admins is that it allows us to put the virtual disks on storage that better matches performance demand. I don't mind configuring iSCSI and Fibre Channel to a SAN, but if I can slap a few virtual disks on a server to house the lower-tier virtual disks, and put them on a cluster that connects over a network share, that would be so much better.
So, SMB 3 is something you should consider, investigate and try out. Perhaps you might find that the old ways of storing your virtual disks (and other large data) can be accessed with a method you never thought of -- over a simple network share. These improvements can help your virtualization deployment continue to move forward and mature gracefully.
Meanwhile, I will still crawl out of bed, creak and pop, to get my coffee.