Archive - 2010

December 31st

namebench

Just ahead of the new year, someone mentioned namebench on slashdot. I've just given it a try - it's dug out some fast public DNS servers, which are *way* faster than the one my ISP gives me, and also faster than OpenDNS.

Why would you care? Well, in most page loads, the DNS lookup is amongst the single slowest component. Whilst namebench isn't quite ready for the average user, it's good for the more tech-savvy, and migh just make your browsing experience a little niftier.

October 16th

Chocolate Unwrapped, Vinopolis, London

Just been along to Chocolate Unwrapped - a bit disappointed. Essentially, it's a load of posh chocolate vendors, hawking their wares. Nothing too wrong with that, except you have to pay £10 each to get in, and be gently sold to. I'd suggest popping along to Selfridges food hall instead.

October 15th

Freedom2Surf / Nildram / Pipex / Opal / TalkTalk - What?

I have long been a customer of Freedom2Surf, after a recommendation from a friend. They've been a great ISP, with excellent technical service from the outset, and generally pretty helpful support on the phone on the vanishingly rare occasions that I've need it.

They have recently been bought by a slew of other people; first it was Pipex, then Opal (aka. TalkTalk). In short, a bunch of ISPs have all been bought up by TalkTalk, who are now starting to offer some new features and facilities through these brands.

A while back, I got an email from Free2Surf, offering me home phone line rental and broadband in the same (pretty attractive) package. The thing is, the sender had managed to spell "Freedom2Surf" incorrectly in his email. Probably just a typo, but you've got to wonder about a company that can't spell it's own name.

Today, someone from Nidram sent me an almost identical email, but had incorrectly abbreviated Freedom2Surf as "E2S". He's also managed to copy all the other customers into the email - so we now all know about each other. I've replied to remind him that I could quite easily just hit 'reply all' and offer a competing product, or else sell the names and emails of his customers to third parties.

I really want Freedom2Surf (or whomever they're called these days) to stay good - please don't let their new corporate overlords dumb them down to the same shoddy levels as so many other ISPs. So far, some training on email and the spell check feature would help, but how long before everything else goes down the pan too?

October 14th

Stuff Today

Stuff I bumped into today that I like include assembly instructions from hell (which resonates as I've got some flat-pack to assemble at the moment), and this picture (on this round up of similar items) - all via da Rivets.

October 6th

IPv6

IANA are stating that they're running out of IPv4 addresses to give people to use on the Internet. IPv6 is apparently the way to resolve this problem, but adoption is very slow.

Some enterprising Kiwi aims to motivate us to migrate: http://www.ipv6porn.co.nz/

September 30th

Boris Bikes - You've gotta really want to use 'em

The so-called 'boris bikes' are of course the trendy new accessory for London. It's a great idea - you just walk up to a bike, put in your magic key, take the bike out, ride to another bike rack and drop it off. If you can manage that in less than 30 minutes, your journey is free.

Mrs Cat got me a magic key, so this week I thought I'd give it a whirl:

Monday 27th PM: 1 bike left at Earnshaw Street, but not removable from the stand, even though not showing any problems. Took the tube all the way home.

Tuesday 28th PM: 1 bike left at Wardour Street, but not removable from the stand, not showing any problems. Went to Great Marlborough Street, 1 bike left, not usable either. Went to Little Argyl Street and found a bike scheme man trying to get the last remaining bike out of the stand. Took the tube all the way home.

Wednesday 29th PM: Absolutely peeing with rain - took the tube home!

Thursday 30th AM: Bright sunny morning, so decided to get off at Pimlico and use a bike. Went to St. Georges Square because the Internet showed lots of bikes remaining, only to find the entire stand wasn't working (and three other people lurking around with the same problem). I checked the display which said the next nearest stand (Rampayne Street) had 9 bikes on it. Found one bike remaining, which wouldn't come off the stand. Went to Regency Street, found lots of bikes, although another user was saying the first one he'd tried wouldn't come off the stand. Managed to get a bike, cycled to Earnshaw Street to drop it off, but it was full, so headed to the British Museum as it was the nearest showing empty spaces (although the very next nearest was full).

Edit: Thursday 30th PM: One bike left at Earnshaw street, the unlock light went green, but try as I might, I couldn't get it off the stand. Walked around to Russell Square, lots of bikes, and people getting them in and out, except my key just kept showing red on all of them. Walked on to the British Museum and found lots of bikes and got one out no problems. Dropped it off at Vauxhall tube with no problems either.

I'm going to keep trying with this, but man oh man, you've really got to want to use these bikes to actually be able to use them. In short, you'll end up going somewhere you're not near to get a bike, then end up dropping it off somewhere you don't want to go.

That said, possibly because they're all sparkly and new, the bikes are quite nice. They're big old clunkers, mind you - they're heavy, a bit non-responsive, and the brakes and gears aren't very good. However, for a quick trip, they're just what you need - if you can find one, and don't end up going further than you wanted to drop it off!

September 27th

KVM VMs - Sysadmin+

I'm getting to grips with VM management. It all seemed easy enough - just create some VMs and get going. In practice, it's nearly as easy as that, but there are some gotchas you've got to keep an eye on.

The gotchas are mostly to do with guest OSes and kernels. I've found, for example that kernel-2.6.34.6-54.fc13.x86_64 works just fine, but a system running kernel-2.6.34.7-56.fc13.x86_64 will constantly consume 15-20% CPU on the hypervisor, even if the guest is completely idle. Likewise, some Centos guests will consume about 30% CPU on the hypervisor, unless you add in some settings to drop it down to <5%.

In my particular case, I'm using KVM as my hypervisor, which has a few foibles. Networking proved to be a big one for me - the semi-default "virtio" networking is great, but doesn't perform as well as using "tunctl" TAPs. When I say it doesn't perform, I really mean it too - a VM web server, talking to a VM MySQL server on the same physical box went painfully slowly, but with TAPs in place, it's going super-fast (tips on how to do it here).

The pros, on the other hand are that you can fiddle about with systems like crazy and if it all goes wrong, you can revert it back in minutes. For example, in trying to work out why one of my VMs consumed so much CPU, I was able to build, upgrade, rebuild, downgrade, boot, reboot and re-network a VM really quickly and really easily. There are umpteen snapshot and backup options, as well as cloning and rescuing options, all of which give you a lot of flexibility.

Also, if you want to run some graphical VMs (either Linux or Windows), then you can do that and get a VNC server specifically for your VM - and all the while, your VM "thinks" it's got a graphics card all to itself. That's really handy if your VMs are hidden away in a computer room or something (*ahem* the loft *ahem*).

So I'm really enjoying virtualisation, but it's by no means "install and forget" - it takes a bit of care and attention in some new places you're probably not expecting. It's still well worth it though...

September 23rd

Teamviewer Scam

Mumma Cat got caught up in a "Teamviewer scam". Someone called her claiming to be from "the ISP", saying something about them working for BT, TalkTalk and some others. They then said "your computer has over 500 viruses on it, because you don't have any protection". They then got her to turn her computer on and download Teamviewer. The scammers then get remote control access of her computer and show her something that "confirms the problem".

A quick look on t'internet shows lots of people saying the same thing. Apparently the scammers call back, and start asking for money to fix the problem. It's unclear if they install keyloggers, viruses or botnet software on your computer - we're taking no chances.

September 17th

Fedora 13 Servers

It's time for some upgrades to Coofer Cat. I've bought a new machine, and intend to run Virtual Machines on it. For this, I'm going to use a cut-down Fedora 13 installation as the KVM hypervisor, and then build another Fedora 13 system as the web server for the site (I'm going to use other VMs for other jobs, like maybe an Asterisk phone system).

One problem with Fedora these days is that it's primarily a "desktop" product. That means, the default installation adds X Windows, Gnome, and countless tools you wouldn't need on a server. There are "spins" available that do different types of installation, but I couldn't find a "server" install.

To cut a long story short, I've been stripping a Fedora install down to the bare bones. It's got most stuff removed, but has things like RPM, Yum, SSH and a serial port console. I've attached two lists of RPMs - one for a minimal system, the other for the hypervisor. I'm sure there are more packages I could remove, but this seems pretty decent to be going on with. Hopefully this'll save someone else some time if they want to do the same thing...?

September 14th

Upside-down Plants

I got an email from these guys today telling me about an upside down planting solution. I don't know if the photos are all completely legit, but it looks like the plants they've grown are quite happy upside down, even getting their leaves to bend upwards, whilst the flowers grow downwards.