Posts

I’m often asked about how to provision virtual machine disks. This almost always comes down to, “Should I use thick or thin disks?” and then “Should I do thin provisioning on the array or on the hypervisor?” So here we go: Thin vs Thick Thin provisioning: Thin provisioned disks don’t allocate all of the space during the provisioning of the storage. Instead, they allocate the space on demand. This is a great way to get more bang for you buck out of your storage. Let’s take a closer look with an example. ...

I’ve recently had to label more network cables than I care to discuss, but found my mind wondering over the best method to label these cables. I’ve come up with three different ways to label networking cables and wanted to get some thoughts from other Engineers about how they go about this. Method 1: Same label on both sides This method creates 2 labels that are identical and puts one label on each side of the cable. This give the advantage that if you’re running multiple batches of cables all at once, you can determine exactly which cable you’re working with. ...

One of the benefits of using HP Virtual Connect in C-class blade Chassis is the ability to have MAC Addresses and WWNs set on a server bay as opposed to the physical server. I’m sure you’re aware that each device that has a network card has a Media Access Control (MAC) address which is a burned in identifier that makes that NIC unique. HP decided that it might be nice to control those MAC Addresses in their blade chassis. Before you setup any server profiles, you have the option to choose “Virtual Connect Assigned MAC Addresses”. These are addresses that are assigned to each server bay so that no matter what blade is put into the bay, the MAC addresses will stay the same. You might find this very useful in the case of a failed blade. If you receive a new blade from HP and throw it into the same bay, it will retain all of the same MAC Addresses and thus look the same to your switches. ...

One of the new features I really wanted to check out in Server 2012 was the ability to setup a highly available DHCP server. Prior to Windows 2012 if you wanted to setup a highly available DHCP solution, you only had a couple of options. 1. You could setup up a split scope, which required you to setup identical DHCP scopes on two servers, and then adding exclusion ranges on each of them so they didn’t both hand out the same IP Addresses. Usually this was done in an 80/20 fashion. ...

I often hear Port Address Translation (PAT)referred to as Network Address Translation (NAT). Its a pretty common to hear this and is really not a big deal because the two are similar and I know what is meant. But to clear things up I decided to put together a quick post. Network Address Translation NAT is the process of “translating” an IP Address in a router or firewall. This is most commonly done to present a private IP Address into a Public IP Address that is accessible on the Internet. For instance, you may want to have your E-mail server have a public address so that it can route mail. ...

I was recently integrating Veeam Backups with HP Data Protector for a backup project when I found a great Powershell command that I didn’t know about. Invoke-Command -comp [computername] –scriptblock {script} If you’re familiar with PSExec.exe this is an equivalent powershell command, but if you’re not, this command will allow you to execute something on another machine. Veeam has the ability to call a script when a backup job completes, but I needed a different server to execute that script. ...

It’s hard to believe but theITHollow.com is now 1 year old! The first year has been great and I feel like I’ve probably learned more writing it than the readers have learned from reading it. Thank you for a great first year and if you keep reading it, I’ll keep writing it.

There was some exciting news released today so I wanted to get it in a post in case you hadn’t heard about it yet. The HP Global Partner Conference is going on in Vegas and they release some new gear to accentuate their converged infrastructure model. A new BladeSystem Platinum was announced which will include the options for infiniband, 16Gb Fibre Channel, and 40Gb Ethernet! If you’d like more information about the new BladeSystem Platinum please check out HP’s video. ...

If you’re an engineer and you’re trying to get more experience with a variety of different storage devices, you might find yourself in a bit of a pickle. Most customers settle one one or two storage vendors and that’s it. So if you work for one of these companies you can learn EMC or Netapp, etc. I highly doubt your company would be interested in purchases a few different types of storage devices so that you can learn them as they are quite expensive. ...

Oh Noes! I sense lolcats in this post. I’ve been seeing Category 6a cable if a few datacenters recently and thought it might be a good idea to review when and why we would use this type of cabling. Wiring The Category 6a cabling is wired the same as Category 5e at 1000BaseTX speeds. Note: that you can get away with splitting two sets of pairs off of Cat5e, but this only allows 100BaseT Ethernet. ...