Older blog entries for Stevey (starting at number 190)

Network Diagramming with Dia

After my previous lament over the lack of a decent diagramming tool for drawing pictures of networks several people pointed me at a GNOME-based tool called dia.

Dia is a portable application which runs on on Windows too, via a complete download containing zlib, gtk, etc. In short the windows download contains everything you need to get it running in one simple package.

It's a little reminiscent of the GIMP in the sense that it starts up with a blank canvas and a window with all the tools on it.

Right clicking upon the canvas allows some options to be applied. Clicking upon a shape in the tool window allows you to place it upon the canvas.

The tools are arranged in logical groups, Electronics, Cisco - Networking, etc. This makes it easy to work with a set or related images and keeps the display nice and clean.

Top level tools like different line drawing items, the text tool, etc are always visible which is very useful.

The files are saved as zlib compressed XML files, which I'm assuming means that they are possible to create via clever perl scripts if you needed to.

The application exports to PNG, JPG, SVG, EPS, PS, and several other formats.

In short this is a lovely application to use and a real credit to it's authors.

It's not often I see a program I've not heard of before and discover it's wonderful. I have literally no complaints about it at all.

That's probably enough propaganda - I redid my network diagram using it, so theres a very simple sample. (Be gentle it was my first go!)

My Home LAN

I put together a simple writeup of my home network.

Sadly the diagram is in blocky ASCII - I cannot find a decent network diagramming tool for Linux. Maybe I should look harder.

In short: I've now got two desktops, a laptop, and a Sun Netra. All running Debian.

Retro Gaming

I find myself strangely compelled, watching Gameszville (a poor TV gaming show which feels like a cheap and nasty clone of Gamesmaster which featured astronomer extraordinaire Patrick Moore.) because they are having a retro episode.

I love retro gaming.

I would kill things to get an Tetris arcade box - but never find any going cheap locally. I've seen a few online going for a couple of hundred dollars, but the shipping gto the UK would be cripplingly expensive.

Oh, and as a followup to a previous entry I made about Debian shirts - I now have a couple and a nice retro Space Invaders t-shirt.

Apache SSL

I setup my Apache server to use mod-ssl, so that I can have "https protection" for my new webmail installation.

This all works well, (I wrote a guide for this here - Debian specific).), except for prompting for the decryption key when apache starts.

Later I rebooted my machine only to be locked out of it. I guess it's sat there waiting for the password to be entered.

Thankfully I've found out I can avoid this step if I save the password in a file, then modify the Apache setup to read it from there:

echo `mypasswd` > /etc/apache/ssl-password
chown root:root /etc/apache/ssl-password
chmod 600 /etc/apache/ssl-password

 echo >>/etc/apache/get-password <<EOF
#!/bin/sh
cat /etc/apache/ssl-password
EOF
chmod 755 /etc/apache/get-password

This just needs the httpd.conf to be modified to read:

SSLPassPhraseDialog  exec:/etc/apache/get-password

Something to do when I get home.

Controling Bug Reports in Unofficial Debian Packages

I've seen a few people create unofficial packages of software, and leave a disclaimer "don't report bugs using the Debian bug tracking system".

If your users are using reportbug you can specify that its messages go to a specific email address by placing a control file in /usr/share/bug/foo/control.

You can also do clever things like add some boiler plate text to the bug report - useful if you need the user to run a command or two for diagnostics.

I'm guessing this will work for other bug reporting front-ends, although that should probably be tested...

cdrecord

In a coincident to my previous entry Branden Robinson suggested forking cdrecord.

I tested burning an ISO to disc using libburn as contained in Debian and it still works, this is good :)

Later in the week, if I have time, I will look at the cdburning code in some of that applications and see if they have their own code or if they just fork() and exec() cdrecord - if they do that it might be worth writing a wrapper around libburn which handles the same arguments.

CD Burning

It seems like no matter what else you use under Linux you must use cdrecord to ultimately burn your images to blank discs.

It's one of those applications which millions of people use, whilst complaining at the author, joerg schilling, for his licensing and bad attitude.

Seems to me that replacing this application would make many people happy, so why's this not happening?

Lack of interest?

Lack of decent hardware / test discs?

No real grudge, just whining?

I'm guessing that the SCSI stuff is mostly standardized, and that you could probably have a core application with just plugins to handle specific models.

Tonight I will look at the sources ..

Update: Thanks to Joachim Saue for pointing me at libburn which appears to coming along well. I can't access the CVS repository from here, but I suspect that's a local problem..

Backups

It's interesting that I've been reading a lot about backup problems recently, as I've been toying with deploying backup software on a host of machines.

My idea is to have a group of hosts accepting connections from a central backup server (this is the one with the tape drive on it) it will fire out requests for files and suchlike.

The central server is in charge of the scheduling, the reporting, and all communications.

Ideally I'd like to see some kind of efficient protocol, such as 'send me the files which have changed beneath /home'. Instead right now I'm just installing rsync, and ssh.

The central server then juse needs to execute 'rsync -e ssh ...' to backup the remote hosts.

Unfortunately this means that the ssh server must be setup to permit remote root logins. For a LAN this might not be an issue. I guess I could do something like install an additional copy of SSH running on a non-standard port, with only access for root, and only with a public key.

But that seems like an additional hassle.

So far the 'server' is a simple perl script, along with some simple utilities to add and remove cron jobs. The client is a dummy package which just has a manpage, and Depends: upon rsync + ssh.

Seems like it's not good enough for a commercial setup, and too `advanced` for most home users. Still it's working well on my small farm.

Note To Self: Some files are already backed up in /var/backups - knowing this a few years ago would have been useful ;)

Woodwork

Tonight I've been painting a nice wooden chest I made.

Doing manual work is refreshingly simple.

Almost a shame I play with computers so much, I'd like to do real creative physical things more often. I guess I need to manage my time better, and sleep less.

Slashlike

I spent a while today flirting with slash-like weblog / portal software.

By far the simplest to install and use that I found was YAWNS (Yet Another Weblog News System).

This is a Perl-based system using HTML::Template and MySQL, all software I have running on my my website already.

I'm toying with the idea of setting up a Linux/Debian system administration site with little tips, documentation, and mini-howtos.

On the one hand I find it an attractive idea to post all my own experiences and discoveries together, such as how to use openvpn, etc.

On the other hand there is the the Linux documentation project, Debian planet and Debian Help already.

So I guess I'll sit on the idea for a few days, write entries as if I were doing it for real then see how long I keep it up.

Update: - See the current mockup here.

Hardware Woes

Last night I tried to add a new drive (80Gb) to my primary desktop machine, undecided.my.flat.

I powered down the box, fiddled around with cabling until I could physically fit the drive inside the box and then powered it back up.

It's a good job I didn't put the case back together - as nothing worked. No BIOS beep. No drives spinning up. Nothing.

I did the obvious thing, I disconnected the drive I'd just added leaving the machine in the same state as it's been for the past year or two. Nothing.

I have no idea why but the machine refused to boot, or make any kind of noise at all now. It's dead.

Sure I may be a little rough and ready when tinkering with hardware. Sure I may not care about static protection as much as I might but adding a new disk shouldn't fry a machine.

I tested all the connections I could see, unplugged everything that wasn't onboard in a futile attempt to track down the problem.

The power supply is good, the CPU fan comes on, the power lights come on, but no sign of spinning up either the disks, the floppy, or the CD-RW/DVD combo drive.

So I ripped out the original drive, the new drive, the memory and then moved them into the body of my other machine, tara.my.flat. (I had to pull out the single drive in there to fit it in).

So now I have a machine with two drives, two CD-RW/DVD combos, and 512Mb of memory.

Hardware Joys

I'm constantly impressed with the ease at which Linux systems cope with different hardware.

After moving my primary drive from a machine with an onboard SiS chipset to a different host box it came up without any problems.

Sure the networking didn't work, sound was b0rked, and GDM failed to start because X was setup to expect an onboard SiS driver, not the Nvidia card that box had. All that aside it worked well and by bedtime I had a working box, but I was too tired to do much with it.

I setup the NVidia FX5200 with this Debian NVidia HOWTO. Very well written and the whole job took only a few minutes. I'd never heard of module-assistant before now, but it worked wonderfully well.

Getting the onboard NIC going was trivial, Xine continued to play my DVDs once I'd sorted out the sound driver (via82xxx_audio) and I tested that the USB toys I have still worked.

Laptop Fun

I installed GNOME on my laptop to see how well it worked.

It installed a suprisingly large number of packages including abiword, gnumeric, and many more.

This is the first time I've seen/used GNOME in years and I was very pleasantly suprised.

It's not as lightweight as my usual IceWM setup (clearly!) but it was pleasant enough to use. I didn't hate it, even though it would insist on playing movies and music with Totem (which mostly failed) rather than Xine.

I fixed it up as well as I could then declared the rest of the night a computer-free evening.

Ice-cream + Sleep = Happy Steve.

Clothing

Thanks to several kind readers - I know have a group of sources for Debian related clothing available to the UK.

• Open Stuff is a Belgian company with lots of Debian related stuff, and a fantastic Space Invaders shirt!
• Steven McIntyre has some Debian shirts available still and is based in the UK.

I also got pointed to the Debian-UK Cabal, which I'm too scared to investigate further ;)

I think I will look over the Debian site and see if there's an obvious place for this information to be added - I know that there are consultant lists, and other supplier information. It might be worth adding a section if there isn't already, or including UK listings if there is a relevent area for it.

Thanks to everybody that helped - and especially those who didn't chastise me for poor google skillz ;)

PS. When it comes to pimping, I'm hireable for Debian related troubleshooting or setup.... I've worked on big sites such as Machinima.com - stood up to a Slashdotting when I migrated it to Debian :)

Clothing

After reading Daniel Stone talking of wearing a Debian T-shirt I'm reminded that I still don't own one.

Having never been to any of the conferences for distance/expense reasons I've looked online a few times for local (read UK) based suppliers and not found any.

I printed up the open use logo onto a couple of mugs a few months back, I think I made 10 or so and sold 8 of them, keeping two for myself :)

So if anybody can point me at an online store for selling debian branded clothing I'd appreciate it, even better if they donate to the project.

DVD

Another timely piece I read was Steve McIntyre's piece of fitting Sarge onto DVD.

Whilst looking at online suppliers for clothing I came across DebianShop.com and I've mostly made up my mind to buy a copy of Sarge on DVD, as a simple means of getting all the binaries and source for auditing purposes.

I hope that we can get it to fit on a single DVD, honestly I just naively thought it wouldn't be an issue!

Advogato

People seem to be abusing the site, for both attempting to execute Javascript on profile pages (try harder it's possible ;) or for creating link spam.

Sad to see ..