I recently had an issue with vmware’s vCenter where all virtual machines and hosts were showing as “Disconnected”. Nothing could be done in the control panel, but it functioned otherwise. Doing a quick search online, I didn’t see many results, so I restarted the instance, hoping the issue would self-resolve. However, the instance didn’t come back up after a restart. I explain how I resolved the problem, and give general troubleshooting tips to find problems.
I recently got another eight solid state drives in for my second Poweredge R710 (“Lucid”), but was getting a “Virtual disk creation failed!” error when creating the array. Even after wiping the drives of partitions and data, I was still getting the error.
When I moved into my current apartment, I switched to a Dell Optiplex 780 as a router, which worked well for about a year. Power draw was a little higher than I’d like, around 60 watts, but it handled its router duty without any complaints. During a warm day in July 2014, the Optiplex’s power supply exploded, literally. I purchased a Dell Poweredge R410 to replace the Optiplex with the idea that I need something reliable since I work at home all the time. The Poweredge also worked very well as a router, you might even call it overkill, but the power draw and noise got annoying.
A couple weeks ago, I decided to build a low power system that had easily replaceable parts for cheap. Not an easy task to do, but with some help from a friend, I was able to spec a nice system out. Here is what I built:
I had a buddy of mine ask me if I wanted to buy a ton of solid state drives, namely Samsung 830 Pro 256 GB drives. I was initially hesitant, due to the expected price, but quickly found out he wanted to get rid of them cheap. Who am I to say no to a friend in need? 🙂
Hypervisors generally allow creation of virtual devices (sound, USB, network), which will work in most cases. However, if you need more control over the device or more options than the stock virtual device gives, you are going to find yourself stuck. To get around this, PCI passthrough is used to pass a raw device (such as a sound card, RAID card, video card, etc) directly into a virtual machine. This gives unfettered access and to the virtual machine, it is treated as if the hardware were directly connected. In the guide below, I explain how to pass through PCI and USB devices to Xen Cloud virtual machines.