How a wonky DIMM ruined my server upgrade

Friday, December 16th, 2011

As you may be able to see in the highest-resolution version of the snapshot above (click to enlarge), it’s not every day one comes across a physically distorted DIMM.

This is one of a set of eight 4GB sticks, originally intended to boost the performance of a Hyper-V host machine at Ratcliffe & Brown Wines & Spirits, the subject of a forthcoming PC Pro Business Clinic. The server upgrade wasn’t part of the subject, but it pretty quickly turned into a source of aggravation – this bendy SIMM is not immediately apparent until it’s placed on a flat surface, and I tend to land DIMMs on a lump of textile, like a mouse mat or a rucksack; anything but a conductive perfectly flat plane like a rack-mounted server lid.

Surprisingly, it sat in the DIMM slot perfectly well. Unsurprisingly, the server (a Dell PowerEdge 2970) spat the dummy the minute power was restored, quite accurately complaining about “unusable memory” in the scrolling front-panel display.

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Why you might need to reboot your router to see a website

Thursday, July 29th, 2010

Just at holiday season begins, it looks very much as if various service providers and backbone connection suppliers have been very busy.

Lots of services have had their public IP addresses updated; I am getting calls from clients whose internal systems don’t genuinely use a domain name to get to a service. It’s not uncommon for all manner of software products (including router firmware) to let you type in www.pcpro.co.uk, and then look it up at that moment and convert it to 212.100.242.151 – which is what they then store for future connection attempts.

When we decide to change that underlying server address – which isn’t a bad thing to do, it’s a supported and allegedly seamless choice for a connectivity person to make – these various bits of software and hardware that use “one-shot lookup” simply fail to re-connect the PCs behind them.

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First Look: Dell PowerEdge R510 rackmount server

Monday, October 19th, 2009

Announced last Friday, a Dell PowerEdge R510 mid to low-end rackmount server has landed with a light-ish thud in my corporate testbed facility. I might be joking about the corporate testbed, but I’m not joking about the lightness: having just seen the bruises fade away after shifting my stock of HP LP2000Rs (by donating them to the London Cycle Campaign), it was a major relief to be able to carry and unpack the R510 without cups of tea for the battered-shins posse, cursing, and fresh dents in the back of the estate car.

Comparing the R510 with the old machines is hard, because the simple physical similarity wrongfoots you when you actually absorb the statistics. I gave away 5 LP2000R’s – the virtual machine images of them all would fit, and run, inside the R510 without complaint, and use rather less than half of the current required by just one LP2000R.

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All your computer are belong to us

Wednesday, April 1st, 2009

To London’s Charlotte Street Hotel this morning, and the official UK launch event for Intel’s new Xeon 5500 series CPUs – the ones with that ever-so-fast Nehalem architecture in them. (No, it wasn’t a joke. Real things do happen on April 1st.)

It wasn’t the most surprising launch of a server processor ever, but server events aren’t usually renowned for thrills and spills.

Some interesting figures emerged though. They show in just two slides the market reality behind Sun being swallowed up by IBM a few weeks ago, and the sheer dominance of Intel when it comes to processors in everything from enterprise servers to netbooks. (more…)

I like Miso Soup

Tuesday, July 29th, 2008

No, I haven’t been taken over by a random word generator : I genuinely like the stuff. Not just because it perfectly complements some Sashimi or a Bento Box; but because it helps me think about air-conditioning and heat. Miso soup is a mixture of stock – or dashi – with paste – or Miso. It’s supposed to arrive hot, and if you leave it in a coolish room you can see the little particles of paste circulating in an almost textbook perfect case study of convection: something very few people actually believe is really going on around us, despite being taught about it in school (by a mad Welshman with crinkly wavy hair, a la Dilbert, in my case, but I digress)…

When the weather is hot, and I’m standing in people’s server rooms and they are going nuts with fear and loathing about their precious servers going into meltdown, I like to ask them about Miso soup: and if they get all confused (and then angry and then don’t pay my bill), I ask them how much they think the air inside the typical hot-air balloon actually weighs.

Very few get it right: the answer is, about five tons. Once you get that idea into your head, getting emergency cooling for servers sorted out starts to make a good deal more sense – and those elephant’s-trunk so-called aircon units which harassed managers tend to put in as a reflex action during these periods, start to look more like a way to throw kilowatts into the air for very little benefit, than like a smart way to stop your servers going into meltdown.

Got any good “boy stood on the burning deck” stories from extreme heat or wild weather?