Enabling Jumbo Frames means allowing a larger Maximum Transmission Unit (MTU), usually by setting the MTU to 9000. To verify this has worked you can use ping in windows with the -l flag to set the packet size, and the -f flag to set Don’t Fragment flag in the packet. ping my.test.host -f -l 8972 … Read more
I’m not familiar with VMWare, but I do use Xenserver and I have used Hyper-V (R2). With my current Xenserver configuration I have: 8 Dell Poweredge 29xx servers 2 Dell Powerconnect 6248 switches 2 Dell MD3000i SAN (iSCSI) I have setup my switches in a multipath configuration and optimized for iSCSI by: Separating my switches … Read more
Without making enemies on the SAN team, how can I reassure myself and the application developers that our SQL servers aren’t suffering from poorly configured storage? Just use perfmon stats? Other benchmarks like sqlio? In short, there probably isn’t a way to be truly sure. What I would say (I am a SAN admin), is … Read more
First of all, for a (broad) comparison of DAS, NAS and SAN storage see here. There are some common misconceptions about the term “SAN”, which means “Storage Area Network” and as such, strictly speaking, refers only to the communication infrastructure connecting storage devices (disk arrays, tape libraries, etc.) and storage users (servers). However, in common … Read more
First it is best to define the difference between a block device and filesystem. This is easier grasped if you are familiar with UNIX because it makes an objective distinction between the two things. Still the same applies to Windows. A block device is a handle to the raw disk. Such as /dev/sda for a … Read more