Category Archives: Tech

Instrumenting your house

I recently bought a bunch of wireless sensor tags from a guy in California. The little sensors communicate movement and temperature back to a ‘tag manager’ that you plug into your router. There’s then a cute little web/IOS/android app that allows you to configure them and also receive notifications when they get too hot or are moved.

My main reason for doing this is that we keep temperature-sensitive medication in the fridge at home and the paranoia in me wanted some way of knowing if the fridge door has been left open, or that the compressor has failed.

Capture

 

Whilst pretty straightforward to get going, I’ve found configuring them to be a steep learning curve: the UI has an amazing array of configurable options (which is a good thing) but due to the shear number of them and the inherent delay of seeing updates it can be a bit confusing to see the results of your fiddling. I was also thrown by the fact the temperature sensor in the tags needed calibrating first. The power state of the tags also seems to vary wildly, perhaps that’s related to the cold of the fridge, which makes it difficult to know how long the battery is going to last.

I’m still not yet at the level where I completely trust the tags to alert me when something bad has happened but I don’t think it’ll be too long until that’s the case, but if you’re looking for a neat little solution that tells you where things are, or how hot something is, I think these are definitely worth a punt.

 

The following service is taking more than 4 minutes to start and may have stopped responding

I recently bought a new Canon all-in-one to replace an ageing Canon inkjet and separate flatbed scanner and although the printer itself is pretty good the software leaves a lot to be desired, but it’s usable.

Today I noticed that after restarting for patching my Windows 7 desktop sat preparing to install updates for 10 minutes, which was odd. I put it down to the updates but further restarts today gave similar systems – 10 minute waits for the desktop.

The event log flagged:

Event ID: 7022
Source: Service Control Manager
Type: Error
Description: Server service hung on startup.

and:

The following service is taking more than 4 minutes to start and may have stopped responding: Server

A bit of searching led me to KB319127 which is still applicable to Windows 7 (although the reg keys are slightly different). Having added in the spooler service as a dependency on the server service, the machine now starts in a normal time. Obviously the same weirdness with the vendors mentioned in the KB article is still applicable to Canon drivers.

Managing a NetApp filer from Powershell

Have some NetApps? Want to manage them remotely with Powershell? Upset by the shocking level of documentation? Read on for some common uses:

Connect
If you have your devices domain joined and use a separate account to your desktop login to manage them you’ll need to supply a separate set of credentials:

Connect-NaController -name netapp1 -Credential (Get-Credential) -HTTPS

Create a new volume
Create a new thin provisioned (space reservation=none) volume in an aggregate:

New-NaVol -name testvol1 -Aggregate aggr1 -SpaceReserve none -size 1tb
Create a new QTree, lookup a QTree
Create, manage the option on and lookup a QTree:
New-NaQtree -Path /vol/vol1/homedirs10GBquota01
Set-NaQtree -Path /vol/vol1/homedirs10GBquota01 -OpLocks enabled -SecurityStyle mixed
Get-NAQtree -VolumeName vol1
Create a quota
Add a user quota and lookup quotas set on a QTree. Note the strange syntax for -Volume (it is the volume’s name not full path (/vol/vol1 etc). Also remember that NetApp’s idea of what constitutes a gigabyte is different to everyone else’s so you may want to specify in megabytes instead.
Add-NaQuota -Volume vol1 -Qtree homedirs10GBquota01 -Type user -Target * -DiskLimit 10g
Get-NaQuota -Volume vol1 -Qtree homedirs8GBquota01 -Type user -Target *

Add search paths for auto home shares
List the current paths and add a new one. Important! This command is not additive, you will need to specify any existing paths as well as your new one. This is the same as reading/updating cifs_homedir.cfg

get-nacifshomedirectory
set-nacifshomedirectory -Paths /vol/vol1/qtree1,/vol/vol1/qtree2

Add API access for a restricted subset of users to query a home directory location on the filer
If you want a small set of users to be able to view the location on the filer where it thinks a user’s home directory is, you’ll need to create a custom role with the following API access:

login-http-admin,api-cifs-homedir-paths-get,api-cifs-homedir-path-get-for-user,api-system-get-ontapi-version,api-system-get-version

 

I’ll update with any other useful ones as I find them. I find the cmdlet namespace confusing for NetApp and a lot of commands have different switches for relatively similar things. The API access is also woefully documented.

Site updated

I’ve moved the site away from the ancient and wheezy Movable Type over to WordPress.

Most things have been preserved except the galleries which I’m going to leave up at Flickr from now on. Sorry if this breaks anything but URLs aren’t forever!

Why you should FriendFeed

FriendFeed is hard to explain – it’s like a cross between a forum. twitter and facebook. But it’s better than that: FriendFeed draws in all your content from all the other places you hang out including Twitter, Facebook, YouTube, your own blog (via RSS) and presents it in one place. People can then comment on those posts and you can follow other people’s content.

I admit that it has a bit of a geeky leaning (mostly IT losers like myself and photographers) but the cool thing is that you can get to see content the friends-of-friends like too, exposing you to whole new range of people. It’s fun!

Why you should use FriendFeed if you use:

Facebook:

Do you share stuff (links, notes) on Facebook? FF is a damn easier to do that with (they have a funky sharing bookmark tool). Oh and that commenting / liking thing Facebook has? Where do you think they nicked it from. There’s even a FF app for Facebook so you can share your FF stream with FB.

Twitter:

Not only is the FF / Twitter integration instant, but FF makes a much better Twitter client. FF is also real time, so you see posts scrolling past as they happen. FF also unpicks shortened URLs and embeds twtitpics automatically so you see it all in one place. FF can also “Tweetcast” your FF posts/comments/likes so you can still reach out to your Twitter followers.

Google Reader:

I know reader has some social networking features, but they’re pretty late to the party. Why not post your reading matter into FF for all to see rather than have people guess at obfuscated URLs? Now that reader and FF use PubSubHubbub, your shares and likes in reader show up instantly in FF.

 

You don’t even need to create an account if you use Twitter, Facebook or Google – just sign in with the account you already have. What’s to lose?!

Lastly, I’ve found the team behind FriendFeed to be the most receptive and responsive bunch of developers I’ve ever come across. New features come out regularly (like groups and friend lists recently). There’s a neat new API for people who like to tinker (my mini blog on the left there is driven using the v1 API).

Oh, and there are never any spammers or trolls :)

If you do signup, be sure to follow me and I can point you in the direction of some good people to follow too (another new feature: suggested friends!): http://friendfeed.com/alexlomas

MovableType 4

Not posted for a while, not least because I’ve been putting off doing the upgrade from MovableType 3 to 4. I came across problems with the DB migration (UTF-8 please), new templates, conflicting CSS – nightmare.

Many tears later it’s roughly complete. Please give me a shout if something seems bust.

I give up trying to stay up to date with technology.

Windows 7 Media Centre

win7mediacenter

I did an in-place upgrade of our living room media centre to the Windows 7 RC last weekend. I was a bit hesitant, not least because it’s our main TV and therefore has to have a high wife-acceptance-factor (WAF>90). I had updated to Vista TV Pack a few weeks ago and found some issues with reception of a few channels (C4 mostly) so I felt that things probably couldn’t be any worse.

The upgrade went amazingly smoothly and things pretty much "just worked". I had to update my network card drivers as they blue screened on standby, but they were 2 years old. The iMon LCD display also doesn’t work as their app crashes on startup. I presume an updated version will emerge sooner or later.

But, down to the good bits:

– If you hadn’t already gone to Vista TV Pack, then you’ll get interactive ("red button") on DVB-T and subtitles.
– Speaking of subs, when you mute media centre, subs get turned on automatically. Neat.
– TV quality looks better, a bit sharper perhaps.
– I love the new screensaver of your favourite pics / cover art when TV is paused or stopped.
– In the guide, hold down the arrow keys and you’ll super-speed through the days.
– The now/next mini guide is much improved for browsing around channels.
– The new movies section automatically categorises and grabs cover art for any movies you record from TV or play back via DVD.

The only thing I don’t like is the media centre startup noise. It sounds like Fox News’ jingle or some American anthem. At least you don’t have to hear it that often.

HTPC

I’ve just finished building a media centre PC. I’ve wanted to be able to do timeshifting and simultaneous recording of TV for a while and the added benefit of using a Vista box to do this is that I can play all my music and HD content too.

A quick overview of the components I used:

Zalman HD160+ HTPC Case
Zalman ZM600 600W PSU
Zalman CNPS9500 CPU cooler
Samsung Writemaster DVD
Gigabyte Radeon HD4550 graphics
Gigabyte GA-X48-DS4 motherboard
Intel Core 2 Duo E8500 CPU
Samsung 1TB Spinpoint
4GB DDR2 RAM
Hauppuage Nova-T 500 PCI dual tuner
Acoustipack soundproofing material

It’s not quite the ultra silent PC I was after, but it’s not too bad. The only noise is a small bit of CPU fan noise. At the moment it doesn’t fit into my AV cabinet under the TV (the case is pretty big.) but if I get another one in the future then that should really help cut down on the audible noise.