A few weeks ago I bought a pair of Devolo 500AV Ethernet over mains units
to replace/extend a pair of 200AV units I already had. Someone asked if could
use iperf to see how much faster they were.
To baseline what I had I ran the test from my desktop to my server over a 1 Gig switch and the most I could get was a feeble 333 GBit/s. I then tried from my laptop to the server on the same switch and that got a much better 740 GBit/s. The Marvell Yukon card on my desktop is a PCI device and the JMC250 in the laptop is a PCI-e so that may partially explain the differences.
Trying my laptop to the server via a 200AV/500AV/Gig-E switch gave a throughput of 56 GBit/s - about what you would expect. I then tried the laptop through a combination of 500AV/500AV/Gig-E but that wouldn't work as the JMC250 refuses to detect the 500AV. I then tried the laptop with different switches, it refuses to talk to my second Gig-E switch or my old Ethernet hub.
After some Goggling it turns out that the JMC NIC is a bit fussy and often fails
to auto-negotiate with some "green" Gig switches, such as in the 500AV or my newest
GBit switch, but is happy with older switches and plain Fast Ethernet. If you
manually set the speed with ethtool then it's okay. I downloaded
the latest driver from JMC and that is a bit better but while it will connect
to my 500AV and my newer Gig-E switch automatically, it won't negotiate the correct
GBit speed, falling to the older 100 MBit setting.
Footnote: The JMC250 is a 1 Gig Ethernet NIC from JMicron Technology Corporation, not something from the Jupiter Mining Corporation...
One of the disk on my home server is reporting issues through SMART,
it's still healthy but it will have to be replaced... The disks are
in a mirrored pair using Linux mdadm so I won't lose
any data if the drive actually dies, but it's a pain as they are
not hot-swappable and it will take a bit of effort.
It's annoying but I suppose I bought the computer with a pair of
disks for just this reason.
While disk drives have got larger since I bought this server and marginally faster they haven't got any cheaper because the recent flooding screwed up the supply chain. SSD disk are just not cheap and reliable enough for a home server yet - though they are a good idea on a laptop or even desktop system.
I'm naturally cautious and careful. I don't like to make rash decisions, I like to carefully weigh my options and do the right thing. I'm very keen to get the very best value for my money, doesn't matter if I'm buying something cheap or expensive I like to get the best value.
Nearly 7 years ago I bought a pair of DNUK desktop computers running Debian. They have been very good and with upgrades have kept going very well over the years. The moving bits on them are now coming to the end of their natural lives, I've lost one PSU and a DVD player already and the CPU cooling fan is a bit noisy now. Their old AGP graphics cards are clearly not up to modern standards and while the single core AMD64 processor was fast when new - they aren't that fast anymore. A new quad core system, with four times as much RAM and faster RAM at that (DDR to DDR3), new graphics and larger faster disks isn't that expensive. I will replace them with the next 18 months - the dilemma is how long to wait to get the most out them and the best new versus a sudden failure and the fact they do feel slow now...
In the same token I have a more expensive dilemma. We bought our house 2 years ago. We knew that the boiler would need replacing. The solar water heater is home made and not to modern standards nor is it linked to the current gas system. The solar system isn't performing well so the current dilemma is when to rip all the antique junk out and replacing it with a modern high efficacy condensing boiler, versus carrying on as we are - again accepting that there may be a sudden failure.
The annoying this is that I know in some respects the £3000 we spend on a boiler would be paid off by the reduced gas costs over 10 years. Just as I know the increased productivity from a faster computer would help (well only a little),
On Sunday night my 7 year old DNUK desktop would not turn off but was clearly not actually on. On Monday I took the PSU out, on Wednesday a friend lent me a spare and the rest of the computer is okay.
Today I've ordered a cheap silent PSU to replace the noisy and now dead one that was originally in there.
Today I thought I'd try out my Canon EF 28 mm f1.8 USM lens on my new camera body. I took my EF 20 mm with me on holiday and thought I'd try out my 28 mm today. I took it of my old Elan IIe (50E) body and put it on the 60D body and went for a walk.
I got to the first picture I wanted to take, lined it up, the focus locked it in, but when I fired the shutter "Err 01" came back on the body! Strange I've never seen that before. Tried again and the same problem. I swapped the 20 mm back in and that was okay.
Back at home I tried the lens out on the new and old body and it worked some of the time but most of the time it didn't. On the newer body you get an error, other older body just goes stupid and needs to be power cycled.
A quick Google suggests that this another mechanically similar Canon lenses are prone to a problem where the aperture leaves stick. See the following on Flickr. I tried the non-invasive approach and it makes a lot of noise, the aperture ring either stays wide open or when it does stop-down it stays stopped-down. It's not a happy bunny...
Thinking back it now explains why the old camera would lock up occasionally. I had put that down to cold screwing with the batteries, but now it looks like it was just the lens sticking.
I can buy a replacement lens for £350 or try to get it fixed. I've just spent about an hour with Google trying to find contact details for a Canon approved service centres in the UK. Looks like I can expect to pay at least £100 for a repair...
Not in a good mood. Need a nice cup of tea to make me feel better I think.
Last year just before Xmas/New Year I bought a cheap Novatech V13 small notebook. Though Novatech say it's made in the UK, it's quite clear that it's actually a Clevo W83T made in China.
Installing Debian on it was interesting, it has no optical disk, so I had to do the install off a USB device or PXE boot over the network. It was happy to boot off the network, but alas the Debian stable kernel didn't have the JMC250 driver in, so the install couldn't proceed. It was happy to boot from an image on a USB hard disk, and after copying a kernel over from Debian testing, I even had a functioning network.
I don't have WiFi at home, my router predates cheap WiFi, and as wires are cheaper, faster and more secure than WiFi I've not bothered to buy a WiFi access point. The Clevo W83T has a fairly new Realtek 8191SE WiFi chip-set. While Realtek provide a driver for Linux, it only went into the 2.6.33 kernel, which isn't yet available in Debian testing.
Today I downloaded the Realtek driver direct (rtl8192se_linux_2.6.0017.0507.2010), built it and loaded into the 2.6.32 kernel I'm running at the moment. Press the right button on the keyboard to activate the WiFi chip-set and the KDE Network Manager now says I have an active WiFi and would I like to join a local network.
Woot!
A few days ago I bought a cheap ATI Radeon AGP graphics card to try and extend the life of my desktop system.
The first bug I encountered was that the OpenGL compositing in KDE4
wasn't stable. I added some extra bits to the xorg.conf
config file that is supposed to help (it didn't seem to on it's own)
and I told KDE4's kwin that it wasn't to do a compositing
compatibility test, it should just do it. With that all in place,
OpenGL worked and everything was fine and dandy.
Yesterday I upgraded my Debian "squeeze" system and AMD/ATI's fglrx
driver was upgraded to version 10-6-1 from 10-5-1. When I restarted
X it crashed horribly. Apparently this is a known bug in Xorg and
you just need to make sure you have BusID "PCI:1:0:0"
(or whatever) set correctly in your xorg.conf file.
Today I diligently updated my xorg.conf file and restarted
X and it worked. However now all KDE4 windows are blank and I can't use
them, so I've gone back to the open-source radeonhd driver until I
can figure out what I need to tweak next to fix it.
Not that I'm complaining, I am running Debian testing and I am playing with fire in using the AMD/ATI official drivers, which are noted for the unreliability...
Our desktop systems use generic Nvidia FX5200 AGP graphics cards. Since I upgraded my desktop to KDE4 I've found that the old FX card isn't really up to the job and runs out of steam quite a bit.
I tried to scrounge a newer card from my LUG but there were none to have, so I broke down and bought a newer AGP card. As AGP is obsolete I didn't have much choice, however I found a cheap enough AMD/ATI powered Sapphire HD3450 card.
After fiddling with X.org to get the right driver loaded, and the Nvidia drivers removed KDE4 started with fancy OpenGL compositing running VERY much quicker. Alas there are some stability problems, but nothing that can't be fixed, I hope!
My dead PC is alive again. DNUK sent out a replacement PSU by currier, and after a few hours of cursing it was all up and running. Nylon rip ties can be a pain to remove without hurting the cables they are holding together. I used Velcro when I put it back together. Yesterday I posted the old PSU back to DNUK as I'm happy that my PC is okay.
All companies have problems, it's all well and good to have reliable kit but how you deal with failure also make one hell of a difference. I have had problems with all three PCs I bought from DNUK: two Iiyama TFT LCD screens had temporary image persistence problems and one PSU has died. However they swapped out the defective parts in all occasions without a problem and with minimal downtime.
This morning my DNUK home server was switched off. I switched it back on, the POST came up and before GRUB had a chance to start it powered off again. I tried again and on the second time GRUB came up, but again it powered down on it's own. As this box is my DNS, DHCP, NTP, WWW, IMAP and backup box this is not so good.
I've sent an email to DNUK, the box is still under warranty, so we'll see what happens...
UPDATE: DNUK got back to my email within an hour, and have dispatched a replacement PSU to see if that fixes the box, otherwise they will take it back and replace bits until it starts to work again. Seeing as I'm very busy at the moment and I'm in a rush this is an acceptable start.
Nearly a decade ago, when I lived in the US, I bought a nylon webbing belt made by Bison Designs. I liked it so much that I bought two more. I used them daily for over 6 years and then the Polyoxymethylene (aka Delrin) buckle on one them died and then to my horror I broke an other one by standing on it.
I ordered replacements from Bison and a few weeks later they turned up in the post, via a proxy as they don't sell outside the US. I liked the replacement though the drape and design on the original belts was better.
After two years of use the buckle on one of the new belts died. This time I wasn't happy, two years isn't very long, a fraction of the time my originals had lasted so I emailed Bison Designs to complain. A nice lady replied and said I should just pop all the broken belts in the post and they'd fix them all. When they say a life time warranty, then really mean it!
Today my belts turned up in the post, all as good as new!
At the start of the is week my Dell Optiplex PC at work died. Well it actually refused to boot, Windows XP got so far but no further. I've been given a new PC to work with instead.
On one hand it's nice to have a new PC, it's marginally faster and the new keyboard is much nicer, on the other I've lost two days to setting it back up again to be useful. The new PC is on the companies new build, so even though I'm still local admin there are things I can't do on this PC that I use to be able to do on the old one.
It's a shame I can't have Linux and I'm forced to have an obsolete Windows system but nothing is perfect...
Flash Gordon Savour of the World wants us to borrow and spend our way out of the debt created problems that the UK is currently in. I've done my best to avoid spending, waiting for the much predicted "deflation" to kick in and send prices into a downward spiral to oblivion - so far I've not noticed only inflation in the things that matter and some mild disflation in tat and other non-essentials.
My antique Dell notebook really is reaching the end of it's useful life, 10 years is good going for a Dell. I don't need a full sized notebook really - I never did in the first place, but a netbook may come in handy. The Acer One is a nice device and Amazon are flogging them for £170, which isn't bad - it's better than the £225 that CeX are selling second hand units for in town.
So far I don't see much discounting in the stuff I want, just trivial tat that people could easily live without. I'll probably hold on as long as I can, no point in throwing money away if there is a real bargain to be had..!
Yesterday we spent a good 2 hours standing in the car park at work as the building was evacuated because of "chemical incident" in the server room. Our clapped out infrastructure struck again, an UPS failed in a fairly destructive way - the battery exploded!
Small/cheap notebooks are all the range since the Asus Eee PC-701 launched. Interestingly many of them come with Linux installed instead of the more typical Microsoft Windows. My current Dell Inspiron is showing it's age, it's way to slow and the case is breaking in quite a few places. I don't use or need a notebook much so I've been unwilling to buy a new full price notebook, even a cheap £300 Dell Inspiron.
The initial Asus created quite a stir and there are now several members of the Eee family and several alternatives from their competitors. The Acer Aspire One looks rather nice and works pretty much out of the box with Debian. Maybe I'll buy one, or then again perhaps I'll not...
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I am not a PC,
I am a free man!
