Entries posted in September 2007

This week has consisted of fighting registrars and doing a bit of hacking on xen-shell, xen-tools, and the chronicle blog compiler.

CJ has done some good work trying to get the code modularised, and I expect between the pair of us we can make things neater and better generally.

I've also fixed a couple of bugs relating to the hard-wiring of device names (/dev/sda, /dev/tty1, etc). These devices are replaced in newer versions of Xen which wants to use /dev/xvc0 and /dev/xvd[a-z] instead.

There's nothing else happening at the moment; I'm just having a lot of fun laughing at our new kitten sliding around on our polished wooden floor!

Chronicle seems to be getting pretty popular which is ironic because it was a quick hack to allow me to post blog entries on a couple of hosted sites - which I've not yet done. Oops.

In other news I'm loving the Nintendo DS at the moment, Megan brought me one back from America on her recent trip and I think a day hasn't passed where one or both of us has played less than 30 minutes each.

I'm annoyed that Sim City DS only allows us to play with one city - right now it is her turn, and I'll have to wait until she's finished with her creation before I can have a go - because otherwise I'll wipe her city out.. :(

Tags: chronicle, nintendo ds, patches, wedding, xen-shell, xen-tools | No comments

Tonight I mostly installed Centos 5 upon dedicated servers in America, for a guy based in Germany. Sometimes people do pay me for work which is nice - this job paid for a small stirling engine :)

Yesterday I mostly implemented a web interface for controlling spam via a proxy server.

Several people seemed interested, so I'll explain what I've done:

• Coded several qpsmtpd plugins for different anti-spam mechanisms on a per-domain basis.
  • Because the stock server only supports global plugins.
• Coded a web interface for users to manage the settings on their domain:
  • Virus scanning.
  • Greylisting.
  • DNSBL.
  • Resolvable from hosts.
  • Reverse DNS

The only part that is missing is the final plugin integration, and some glue to propogate some of the GUI settings to the mail server - since adding a new domain is currently 50% GUI and 50% manual.

Each of the plugins supports whitelisting of addresses or domains, and there is a fair amount of logging detail - some is missing which I need to resolve.

Once that is done and the code is running upon my live server I'm happy to let people use it if they have a spare/non-critical domain they can expirement with...

The next thing to do would be to hook in spam assassin, spambayes, etc, on a per-domain basis with "training" addresses..

Tags: anti-spam, qpsmtpd | No comments

Recently the topic of spam on the Debian lists was revisited. I laugh at somebody who recieves 200 spam messages a day.

Here's my stats for yesterday:

                                          Total Mails    : 6399
                                          Total SPAM     : 6077
                                          Total Accepted : 322

                                          Spam Percentage: 94.97%

That's 6077 mails rejected at SMTP time via my filters, and only 322 mails accepted.

The breakdown of the spam rejected looks like this:

                                  Plugin      Count
--------------------------------------------------------------
                                   dnsbl       3755
                             hosts_allow        724
                             greylisting        661
                       check_earlytalker        303
                          check_spamhelo        238
             require_resolvable_fromhost        219
                           virus::clamav         79
                         check_badrcptto         75
                       check_badmailfrom         23
--------------------------------------------------------------

Tags: anti-spam, anti-virus, spam | No comments

I think I'm about ready to start running my SMTP proxy/filter for people now. I've got two users setup and it seems to be holding up just fine. I've managed to remove the need to manually create things, so I'm capable of adding new domains on the fly.

For my personal mail handling yesterday was the first day I've received over 10,000 messages. These are the stats from yesterday showing what happens at SMTP-time:

Total Mails    : 13302
Total SPAM     : 12620 (bounced back)
Total Accepted : 682
Spam Percentage: 94.87%

So I've dropped 95% of incoming mail at SMTP time, which is a big win. Of the mail which was actually delivered I'd guess that pyzor, razor, and spambayes marked a further 50% of it as spam.

So my proxy needs to do better ... but it's pretty impressive.

TODO: Find people to run as guinea pigs, register a domain, profit.

Tags: anti-spam, anti-virus | No comments

Friday Morning I ordered an 80Gb iPod classic.

Friday Afternoon I discover Apple Cuts Off Linux iPod Users

Saturday / Sunday I follow along on IRC the reverse engineering effort

Progress is being made, but still a little bit away from having a result. In the meantime I'm ripping Megan's cds.

In other news Debian Security Advisories are being held up by missing buildd machines for several archs.

Previously I supported the position that Debian should release for 14+ plus platforms, but given the regular frustrations and delays I'm now of the opinion that we should only release for platforms that have at least two buildds - one for security, and one for regular use.

(Benefit of two? If one dies we can both use the other.)

Finally I'm still doing more SMTP work, and it is going extremely well. The next job is to wire up a payment gateway which is tedious and dull.

Update - Looks like the ipod issue is fixed. kudos to wtbw + nopcode .. and everybody else who put in the work.

Tags: anti-spam, anti-virus, buildd, dsa, ipod | No comments

Thanks to gnupod I can now upload audio tracks to my current ipod. Code is in CVS, and you just need to follow the instructions to make it work. (ie. update the ID in mktunes.pl.

I can write it up if there is any interest...

Tags: gnupod, ipod | No comments

The following companies, or people, are using xen-shell with their Xen hosting product(s):

• xen kibbutz
• xen hosting (me!)
• bit folk
• Datarealm internet services
• Chris Lamb
• Cernio

I'm sure there are more, but I've been lax at keeping track. I do want a list, if only for advertising purposes. I'll update the list here if/when people point out omissions.

In other news yesterday I managed to release security updates for KDM & fetchmail which were missing i386 builds. Not good.

The problem was fixed fairly quickly once it was actually noticed, with the help of Noah. But I did get several angry emails during the wait. *sigh*

It looks like people are starting the notice the downside to having broken security buildd machines which frequently cause these kind of problems for us - so hopefully these kind of errors will diminish in time. (Who am I kidding?)

Tags: buildd, dsa, irritations, security advisories, xen-tools | No comments

GNU Screen rocks, in general, but recently I've been using it a lot for custom applications and have discovered a pair of annoying bugs.

If you're not familiar with it then please read this GNU Screen tutorial - it really is worth getting to know!

Anyway onto the bugs:

• Session names may not start with numbers.
• Session names must be globally unique.

The two are related, but I'm not yet sure whether I should report bugs against the Debian package and the code is sufficiently cryptic that I cannot create a fix yet.

Taking the bugs in reverse order please try this:

screen -S foo
[detach]
screen -S foo2
[detach]

At this point you should have two screen sessions "foo" and "foo2". You should be able to attach to them by running "screen -R foo" or "screen -R foo2". Lets try that:

skx@vain:~$ screen -R foo
There are several suitable screens on:
        22317.foo       (Detached)
        22342.foo2      (Detached)
Type "screen [-d] -r [pid.]tty.host" to resume one of them.

Even though foo should be sufficient to identify a unique screen, the first one, it doesn't let you attach. Nasty.

(Yes, you can attach to it if you use the number/number+name:

screen -R  22317.foo 

The second issue is related. Create a screen session with "screen -S 222". Now try to attach to it with "screen -R 222" - instead of attaching it gives you a brand new screen.

Ugh.

Tags: bugs, gnu screen, screen | No comments

A new release of xen-shell was made last night, which fixes a couple of minor niggles:

• The --control command line flag simply did not work. Now it does.
• The 'uptime' command works with both new and old Xen versions.
• Shell history persists correctly even on unclean shutdown/exit.

Unless there are great demands for additional features I'm now going to regard this project as complete/finished. Certainly it works well enough for myself and my users.

Satisfaction is ...

Tags: satisfaction, xen-shell | No comments

Randomisation is a good thing for media players, but it must be done properly.

What do I mean by this? I mean randomness which only works going forwards.

As an example consider the case where you have several films/videos in a directory and you run this:

xine --loop=shuffle *.mpeg *.avi

This appears to do what you want, showing each film in a random order but it is subtly doing the wrong thing.

If you're watching film "two", having just finished film "five" you'd expect to be able to return to film "five" by pressing "previous"/Page-Up - however that doesn't happen.

Xine decides that "moving backwards" in the playlist means selecting another film at random, rather than the previously viewed film which was selected at random - the two are different - and the current behaviour is both counter-intuitive and plain wrong IMHO.

I forget the name of the media player that I used briefly which also behaved like this, but it was enough to make me abandon it almost immediately.

So, think of the children. If you have a random mode, make sure that going to previous items actually does return to previously played items and not random ones.

Tags: randomness, rants, shuffling, xine | No comments