December 22nd, 2009
Trivium
quote, trivium, logic
"Logic is the art of thinking; grammar, the art of inventing symbols and combining them to express thought; and rhetoric, the art of communicating thought from one mind to another, the adaptation of language to circumstance."
Sister Miriam Joseph
March 3rd, 2009
SCPonly chroot with Ubuntu Hardy 8.04 64-bit
howto how to scponly ubuntu server
This is a quick howto for installing SCPonly on Ubuntu Hardy 64-bit.
Step 1
Firstly, install scponly through apt.
sudo aptitude install scponly
Then, use dpkg-reconfigure to enable the chrooted version, "scponlyc". Answer yes to the rather ominous sounding security message.
sudo dpkg-reconfigure -plow scponly
Then extract and make executable the script to setup the chroot.
cd /usr/share/doc/scponly/setup_chroot
sudo gunzip setup_chroot.sh.gz
sudo chmod +x setup_chroot.sh
This script is fine for 32-bit users, but broken for us 64-bit types, so you'll need to change it slightly. Open it up in your text editor, find the line starting LDSO_LIST and modify as follows.
sudo vim /usr/share/doc/scponly/setup_chroot/setup_chroot.sh
LDSO_LIST="/lib/ld.so /libexec/ld-elf.so /libexec/ld-elf.so.1 /usr/libexec/ld.so /lib/ld-linux.so.2 /usr/libexec/ld-elf.so.1"
Add "/lib/ld-2.7.so", which should result in
LDSO_LIST="/lib/ld-2.7.so /lib/ld.so /libexec/ld-elf.so /libexec/ld-elf.so.1 /usr/libexec/ld.so /lib/ld-linux.so.2 /usr/libexec/ld-elf.so.1"
The script should now run fine. Enter details relevant to you (the defaults are sensible) and change the script to be unexecutable when you've finished.
sudo ./setup_chroot.sh
sudo chmod -x setup_chroot.sh
There used to be a bug to do with the chrooted /dev/null, I didn't find this to be a problem, but in case, you might need to run the following (this assumes you installed your chroot in the default location).
sudo mknod -m 666 /home/scponly/dev/null c 1 3
If you're using a 32-bit system, skip to Step 2
Step 1.1 - fixes for 64-bit
The problem is that some library files needed for a chroot on a 64-bit system aren't included by the setup_chroot.sh script and you'll get errors in /var/log/auth.log like "failed: /usr/lib/sftp-server with error No such file or directory"
You'll need to copy the following files to remedy this.
(This assumes you're still in your scponly chroot directory!)
sudo cp -p /lib/libncurses.so.5 lib/
sudo cp -p /lib/libncurses.so.5 lib/
sudo cp -p /lib/libdl.so.2 lib/
sudo cp -p /lib/libc.so.6 lib/
sudo mkdir lib64
sudo cp -p /lib64/ld-linux-x86-64.so.2 lib64/
Just for the sake of security, edit /etc/shells and remove the line "/usr/bin/scponly", which allows un-chrooted scponly users.
Your chroot should now have everything it needs to run correctly, next you need modify/setup scponly users.
Step 2
To add a user and make their home dir in the chroot.
sudo useradd -d /home/scponly//exampleuser -m -s /usr/sbin/scponlyc exampleuser
Note: The double forward slash is meant to be there!
Then get the users line from /etc/passwd and add it to the chroot passwd file.
tail -n 1 /etc/passwd
sudo vim /home/scponly/etc/passwd
Paste the line in and you should be all set!
January 28th, 2009
Vriesea and clusterage
clusterage, dl360, site, vriesea
The site's gone through another little update in the form of a post filter. In line with what Wordpress and common sense, you can now filter posts on 'Home' by year, month, day and title, like this, for example. Filtering down to the title is really useful because people can now permalink to posts like this and hey, the URLs look pretty.
In other updates, I managed to acquire some Compaq DL360 G1s which I'm currently setting up to run as a test cluster to mess about with. It turned out to be a bit of a pain getting them going as Ubuntu server 8.10 is NOT compatible due to what I think is a RAID controller issue. However, Ubuntu server 8.04 will do just fine (longer support cycle means less fussing too).
Finally, now with exams finished, I've thought up a new project, called Vriesea. Which is a not for profit service aiming to offer internet 'facilities' and hosting to non-profit freedom of speech, internet related, music, media and other worthwhile projects. Thanks to Tim and Evo Hosting for helping out with a domain, I'll be reporting back with some progress in the near future.
January 15th, 2009
Happy Birthday Frank!
birthday frank hosting server site uptime
To Frank, you don't have hotswap drives or PSUs or even a fancy case, but you just keep on going. Congratulations on your uptime birthday!
January 6th, 2009
Minor updates and web junk
apache compsci personal site web
Well, I should really be revising, but alas I've managed to procrastinate again. I've made a few updates to the site that might be of some vague interest.
Before now, I've always had the stance that the user shouldn't ever get to a dead end in a site. As such, I've always made potential 404s just redirect to the Home page. However, it's occured to me that the user should know if they've gone wrong, but more significantly, search engines could pick up the non-existent link and it would get indexed, as it returned a HTTP_200. Another reason is that search engines piss on page rank if they find duplicated content, which is ok in a small amount, but not great if for some reason a broken link gets a load of hits.
I've also sorted proper redirection (maintaining the predicate) from quae.co.uk to www.quae.co.uk, to sort the current www/non-www schizophrenia.
Should anyone be interested, here's the Apache rewrite:
RewriteCond %{HTTP_HOST} ^example.com
RewriteRule ^(.*)$ http://www.example.com$1
Finally, I realised I never properly implemented the "more posts" stuff at the bottom of the Home page, whoops! - I still think there's a much more elegant way of sorting the previous post URLs and "<< more posts" link, I need to sit down and have a think.
And now, here's an interesting video about Google search snippets! (Yes, the crackling sound is VERY annoying.)
December 23rd, 2008
The Kitchen of the Future!
future sci-fi
...from 1967. Still, a hilarious insight into what the past thought might have been. A couple of predictions turned out to be relatively true; I personally quite like the idea of a system that recommends me a menu!
December 23rd, 2008
DiggDialog with Al Gore
I don't really follow Digg (as it' a bit wank) and haven't seen Kevin Rose in a video since "The Broken", but I came across this DiggDialog interview with Al Gore. Quite interesting, even if I don't agree with everything he has to say.
December 17th, 2008
Back Home
code
I managed to forget my railcard, so got a nice £63 penalty fare from Nottingham to St Pancras! In retrospect, I actually could have gotten off the train at the next stop, which would have been Leicester and bought a new cheaper off-peak single. Sod it, I'm home now.
Anyway, I've been having a look at Django and am liking it so far; seems much nicer than all that Rails palaver. The admin functionality is one of the main draws as I HATE coding all the form handling involved in admin panels. I think I'm going to write a little article about set up on OS X with MySQL(db) as it wasn't as simple as it should have been.
December 15th, 2008
I've only gone and signed up to Twitter!
No, not really very exciting news. My username is Immunda, there's a link to my profile in the right column of the site or you can just go here.
November 27th, 2008
Bonobo - Days to Come
lyrics music
Couldn't find a listing of this, so here you go.
Journey set sail was to leave,
Cause I'm only birds & bees,
Lose and news and all things be,
Sunlight garden low red blossoms,
Moon tides of the sea,
When struggling for a magic grain,
We throw life to the winds like rain,
For goodness sake,
Spare your failings and take the ability,
To strengthen,
Our spirit can stimulate all minds,
Blossoms of days to come,
Blossoms of days to come,
Move away from your western guns,
Travel towards eastern suns,
Far above all earthly goals,
A pledge for creation's soul,
Spirit finds fresh morning and the dew of precious things,
Hope is a Phoenix building wings to fly,
And what we wish shall be,
Like a breathe of fresh air,
Safe and secret powers that no love can spare,
Move away from your western guns,
Travel towards eastern suns,
Far above all earthly goals,
A pledge for creation's soul,
Far above all earthly goals,
A pledge for creation's soul,
Move away from your western guns,
Travel towards eastern suns,
Far above all earthly goals,
A pledge for creation's soul,
Move away from your western guns,
Travel towards eastern suns,
Far above all earthly goals,
A pledge for creation's soul,
Far above all earthly goals,
A pledge for creation's soul.
