Bob Plankers

Sometimes computers are counterintuitive. One great case continues to be why a virtual machine with two vCPUs runs more slowly than a virtual machine with one vCPU. Think of virtualization like a movie. A movie is a series of individual frames, but played back the motion looks continuous. It’s the same way with virtual machines. A physical CPU can only run one thing at a time, which means that only one virtual machine can run at a time. So the hypervisor “shares” a CPU by cutting up the CPU time into chunks. Each virtual machine gets a certain chunk to do its thing, and if it gets chunks of CPU often enough it’s like the movie: it seems like the …

Read More

Hmm, just read a post over at virtualization.info about how the latest VMware VirtualCenter build numbers don’t match the web site. I guess I didn’t notice that the web site says build 84782 but my client reports 84767. Yet another detail that didn’t get attended to. It’s always the details that make life miserable. I was talking to another VMware customer the other day who was telling me that they were waiting for Update 1 to come out before they migrated from VI 3.0. At the time I thought that was prudent, but with reports of Update 1 problems on top of this build issue I’d advise anybody running a stable VI 3.0 environment just to stay there.

I made time to apply VMware VirtualCenter 2.5 Update 1 to my test environment. Worked great but it did require a reboot of the VC host at the end. Older VC clients seem to connect just fine to the newer server software, but I upgraded mine anyhow just out of habit. Once that was done I used Update Manager to apply the ESX 3.5 Update 1 patches to my test ESX hosts. The process seems to be getting smoother, as it successfully moved through my test cluster and patched everything. Took a while but it was fire & forget. Overall, looks good so far.

I’ve have a couple of updates for my post about Dell’s SUU 5.4.0 and ESX 3.5. First, “suu -c” will tell you what the updates you need are, but “suu -u” won’t actually apply them. Instead you get an error. While you might think “that sucks!” it’s actually fine, because… It looks like some Dell updates for older servers cannot be applied to a system that’s been up & operational for a long time without a reboot. For me, BIOS updates would complain about not enough contiguous RAM, and RAID controller updates caused ESX to panic with a pink debugger screen of death. A reboot prior to the firmware updates appears to prevent problems. My test environment is two Dell …

Read More