Notes about open source software, computers, other stuff.

Tag: Ubuntu (Page 2 of 4)

Fixing the compose key in Emacs on Ubuntu 13.10

After upgrading to Ubuntu 13.10 some time ago I noticed that my compose key (i.e. the key that you press followed by e.g. c and , to create a ç) didn’t work anymore in Emacs. I found two bug reports on this issue [1, 2], both effectively suggesting the same solution: start Emacs like this

XMODIFIERS=@im=none emacs

So I added the following line to my ~/.zshrc and ~/.bashrc files:

alias emacs='XMODIFIERS=@im=none emacs'

(of course somewhere before I set my EDITOR variable). I also changed the command in the launcher I use (GLX-Dock/Cairo-Dock).
This doesn’t make it a system-wide (or even user-wide) fix, e.g. the Firefox add-on “It’s all text” doesn’t get it, but it covers most of my use cases.

ProbABEL v0.4.2 released

During the Christmas holidays I released a new version of ProbABEL (v0.4.2). The official release announcement can be found here. ProbABEL is a toolset that allows running GWAS (Genome-Wide Association Studies) in a fast and efficient manner. It implements regression using the linear, logistic or Cox proportional hazards models.

This version is mostly a bug fix release. The most important user-visible change is the fact that the ‘official’ name for the wrapper script that runs a GWAS over a range of chromosomes is now called probabel instead of probabel.pl. This change was induced by my attempts to get ProbABEL packaged in the Debian Linux repositories. One of the warnings that occurred during the package creation process was a Lintian warning that said that scripts with ‘language extensions’ are not allowed. There are several reasons for that, but the one I found most compelling was the fact that the user shouldn’t be concerned with the programming/scripting language we used to write it in. Moreover, being ‘agnostic’ in this matter also allows us to write such a script in a different language.
Of course, we have left the original name in place (via a symlink) in order not to disrupt any current pipelines. If the user runs the script with the old name a warning appears, urging him/her to start using the new name and that the old name will be deprecated in the future.

In the mean time, ProbABEL v0.4.1 has been accepted in Debian (unstable) and as of today it is also available in Debian ‘testing’. Lots of thanks to the Debian Med team that helped me a lot in preparing the .deb package. Note that the package has been split up in probabel (architecture-dependent files) and probabel-examples (with architecture independent files: the examples). See the Debian Package Tracking System page for ProbABEL for more details of the package.

From Debian the package has trickled down to Ubuntu as well (Launchpad page here), so it will be available by default in the next Ubuntu release (14.04, a.k.a. Trusty Tahr).

Puppet commands change when upgrading to v3.0.0

After upgrading Puppet from versions < v3 to version 3.0.0 or higher, the main commands have changed, keep this in mind when reading my earlier post. From the ChangeLog:

Pre-2.6 Post-2.6
puppetmasterd puppet master
puppetd puppet agent
puppet puppet apply
puppetca puppet cert
ralsh puppet resource
puppetrun puppet kick
puppetqd puppet queue
filebucket puppet filebucket
puppetdoc puppet doc
pi puppet describe

Some examples

To run puppet on a client puppetd --test is changed to:

puppet agent --test

To show a list of clients waiting for signing of their certificates run the following on the master:

puppet cert list

instead of puppet ca -l. To list all certificates, run (on the master):

puppet cert list --all

To completely remove a client’s certificate on the master run:

puppet cert clean client.localdomain

and to sign a client certificate on the master run:

puppet cert sign client.localdomain

Showing other users (from LDAP) in the LightDM greeter

Ubuntu Linux uses the LightDM greeter (the login screen you see after booting). Since I’m using an LDAP server to store my user accounts and LightDM by default only shows local users I needed to tell LightDM to give me an ‘other user’ option where I can enter a user name and password (I first checked to see if my LDAP connection work by logging in with an LDAP user from the console (tty1).
LightDM is configured in /etc/lightdm/lightdm.conf, but also provides command line tools to set the options. To show the ‘other user’ use:

sudo /usr/lib/lightdm/lightdm-set-defaults --show-manual-login true

This will disable the user list. It adds the line

greeter-show-manual-login=true

to the lightdm.conf file.
If you only want to see the “Other” entry run:

sudo /usr/lib/lightdm/lightdm-set-defaults --hide-users true

And lastly you can turn off guest:

sudo /usr/lib/lightdm/lightdm-set-defaults --allow-guest false

Thanks to mfish at askubuntu.com!

ProbABEL v0.4.1 released

Last week I released v0.4.1 of ProbABEL, just a few days after releasing v0.4.0, which contained a small, but irritating bug.

This release took quite some time to create, but features quite a few bug fixes, including a major one: for the first time since the filevector format was introduced somewhere in 2009/2010, the Cox proportional hazards regression module works with filevector/DatABEL files. This is a major step forward, because up till now we had to maintain two branches of code: trunk, with all the regular updates and improvements, and the old branch that contained the Cox PH module that was only capable of reading text files.

Another notable change is the incorporation of \chi^2 values in the output files. At the moment these are based on the LRT (likelihood ratio test), except where that doesn’t make sense (e.g. when using the --mmscore option. The implementation was relatively easy, because part of the code was still there from previous versions; it was disabled however, because it didn’t deal with missing genotype data. Now it does. Using the LRT is also easier in the case of the 2df (or genotypic) genetic model, where using the Wald test is not straightforward.

The third user-visible change was a change in the [code]probabel.pl[/code] script that hides some of the details (e.g. the location of the files with genotype data) of running a regression for the user. Previously, using the -o option meant that the output file name was constructed from the name of the phenotype file, the argument of the -o option and a fixed extension that depends on the model(s) being run. Starting with v.0.4.0 this behaviour has changed. If the -o option is specified its argument is used as the start of the output file name, with only the fixed extension appended to it. This allows users to specify output in a different directory than the one where the phenotype file was created.

Packages for Ubuntu Linux (or one of its derivatives and probably also Debian) can be found in the GenABEL PPA (personal package archive). Previously we also released pre-compiled Windows binaries, but I’ve stopped doing that. They were never tested anyway, and I think there isn’t much demand for them anyway. Most people who do genome-wide association studies use Linux servers anyway.

Development of ProbABEL (and other members of the GenABEL suite) takes place on this R-forge page. If you are in search of an open source project to contribute to, feel free to contact us!

User support for the GenABEL suite can be found at our forum.

Using BibTeX from org-mode

I use Emacsorg-mode a lot for writing notes, todo lists, presentations and writing short reports. Recently I started writing a larger report which I normally would have done in LaTeX. This time, since the notes related to the project were already in org format, I decided to write the whole report in org-mode. The one thing I needed for that was using BibTeX bibliographies (and RefTeX) from org-mode. A quick web search revealed that that can easily be done by adding the following to your .emacs file:

;; Configure RefTeX for use with org-mode. At the end of your
;; org-mode file you need to insert your style and bib file:
;; \bibliographystyle{plain}
;; \bibliography{ProbePosition}
;; See http://www.mfasold.net/blog/2009/02/using-emacs-org-mode-to-draft-papers/
(defun org-mode-reftex-setup ()
  (load-library "reftex")
  (and (buffer-file-name)
       (file-exists-p (buffer-file-name))
       (reftex-parse-all))
  (define-key org-mode-map (kbd "C-c )") 'reftex-citation)
  )
(add-hook 'org-mode-hook 'org-mode-reftex-setup)

After that, RefTeX works, but exporting the org document to PDF (via LaTeX) didn’t include the bibliography entries. A quick look at the error log showed that bibtex hadn’t been run, so the question was: how to tell org-mode to do that too when exporting. The answer is to tell org-mode to use the latexmk Perl script (on Debian/Ubuntu it is easily installed from the package repositories) when exporting to PDF. I added the following lines to my .emacs file:

;; Use latexmk for PDF export
(setq org-latex-to-pdf-process (list "latexmk -pdf -bibtex %f"))

Setting up (or fixing) an encrypted swap partition

Today I tried to clone my laptop’s harddrive to a new drive (thanks to Lenovo for sending me a replacement since the old drive was showing signs of breaking down). At first I tried dd, but that failed at around 90%, either because the old disk is indeed failing or because something fishy with the USB connection or enclosure in which I put the new disk. So I started gparted to check which partitions were copied OK and which weren’t. It turns out that all partitions were fine, except for my (encrypted) swap partition. gparted didn’t even recognise the partition type (on the original drive!). So after I replaced the harddrive I wanted to recreate the encrypted swap partition. It turn’s out to be easy if you follow the steps outlined in this blog post from Puny Geek. Thanks Puny Geek!

Fixing the NFS check plugin in Nagios (in Ubuntu)

For some time (probably after an upgrade, I actually don’t remember anymore) we had problems with the NFS check in Nagios on our Ubuntu 12.04 servers. The check would return UNKNOWN: RPC program nfs udp is not running. When running the actual check from the command line:

/usr/lib/nagios/plugins/check_rpc -H '$HOSTADDRESS$' -C nfs -c2,3

the output would be: Can't fork for rpcinfo.
It turns out that the file /usr/lib/nagios/plugins/utils.pm has the wrong path to the rpcinfo binary. Instead of /usr/sbin/rpcinfo it lists /usr/bin/rpcinfo. So, like most of the times, the fix is easy, but pinpointing the exact problem isn’t.

Don’t forget to restart Nagios after changing the path as utils.pm needs to be reloaded.

As Ubuntu is based on Debian, I expect this fix to work there as well. According to this Launchpad bug report this issue was fixed in January in version 1.4.16-1ubuntu1 of the nagios-plugins package, which is not in Ubuntu 12.04.

Converting from bzr to git

I’m in the process of moving several of my projects that used Bazaar (bzr) for revision control to Git. Converting a repository from bzr to git is very easy when using the fastimport package. In a Debian-based distribution run the following command to install the package (don’t be fooled by its name, it also contains the fastexport option):

sudo aptitude install bzr-fastimport

The go into the directory that contains your bzr repo and run:

git init
bzr fast-export `pwd` | git fast-import 

You can now check a few things, e.g. running git log to see whether the change log was imported correctly. This is also the moment to move the content of your .bzrignore file to a .gitignore file.

If all is well, let’s clean up:

rm -r .bzr 
git reset HEAD

Thanks to Ron DuPlain for his post here, from which I got most of this info.

Solving “RTNETLINK answers: File exists” when running ifup

On a server with multiple network cards I tried to configure the eth3 interface by editing /etc/network/interfaces (this was an Ubuntu 12.04 machine).

This was the contents of /etc/networking/interfaces:

# The loopback network interface
auto lo
iface lo inet loopback

auto eth0
iface eth0 inet static
        address xxx.yyy.zzz.mmm
        netmask 255.255.255.0
        gateway xxx.yyy.zzz.1
        dns-nameservers xxx.yyy.zzz.aaa xxx.yyy.zzz.bbb
        dns-search mydomain.nl

auto eth3
iface eth3 inet static
        address 192.168.4.1
        netmask 255.255.255.0
        gateway 192.168.4.1

When I tried to bring the interface up I got an error message:

$ ifup eth3
RTNETLINK answers: File exists
Failed to bring up eth3.

It took me a while to figure it out, but the problem was the gw line in the eth3 entry. Of course you can only have one default gateway in your setup. I missed this because I was also trying to add routes to networks behind the machine on the other end of eth3.
In the end, removing the gw line in the eth3 entry solved the problem.

My final /etc/networking/interfaces looks like this:

# The loopback network interface
auto lo
iface lo inet loopback

auto eth0
iface eth0 inet static
        address xxx.yyy.zzz.mmm
        netmask 255.255.255.0
        gateway xxx.yyy.zzz.1
        dns-nameservers xxx.yyy.zzz.aaa xxx.yyy.zzz.bbb
        dns-search mydomain.nl

auto eth3
iface eth3 inet static
        address 192.168.4.1
        netmask 255.255.255.0
        post-up /sbin/route add -net 192.168.1.0 netmask 255.255.255.0 gw 192.168.4.250
        post-up /sbin/route add -net 192.168.2.0 netmask 255.255.255.0 gw 192.168.4.250
        post-up /sbin/route add -net 192.168.3.0 netmask 255.255.255.0 gw 192.168.4.250
        post-down /sbin/route del -net 192.168.1.0 netmask 255.255.255.0
        post-down /sbin/route del -net 192.168.2.0 netmask 255.255.255.0
        post-down /sbin/route del -net 192.168.3.0 netmask 255.255.255.0

Update 2013-08-19: Removed network entries as per Ville’s suggestion.

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