Linux

Was playing around running multiple threads in Python. Here is a part of script launching docker_cleanup(controller_name) function in a separate thread.

from threading import Thread
...
    threads = []
    for controller_name in controllers:
        # Remove container if it already exists
        t = Thread(target=docker_cleanup, args=(controller_name))
        threads.append(t)
        t.start()
    for t in threads:
        t.join()  # Block main thread while childs executed
...

Recently hit quite an annoying bug in vmbuilder, tool that allows to build Ubuntu based virtual machines.

Was trying to build a VM using the following command:

vmbuilder kvm ubuntu --suite trusty --flavour virtual --arch amd64 --mem 8192 --rootsize 8000 --dest /var/lib/libvirt/images --libvirt qemu:///system --hostname new-host --user jenkins --name jenkins --pass <jenkins_user_password> --addpkg openssh-server --addpkg git --addpkg acpid

but kernel installation failed with the following error:

Unpacking linux-image-virtual (3.13.0.53.60) ...
, stderr: grep: /proc/cpuinfo: No such file or directory
This kernel does not support a non-PAE CPU.

Discovered an interesting thing today playing around find linux command.

The idea was to process several files in a directory using some utility that directs output to stdout. In order to keep tracking it’s useful to have a status file with a list of already processed files.

Wasted lot of time today trying to figure out why ssh on some server still allows to log in with password despite the fact that in /etc/ssh/sshd_config password based log in is disabled:

PasswordAuthentication no

Was choosing a Linux distro for new workstation. Decided to try Ubuntu 14.04.2 desktop on virtual server first and I think I’ll use Fedora 21. I was unable to configure encrypted volumes in conjunction with LVM using Ubuntu 14.04 desktop installer. Here is an instruction how to configure it manually but, hey, I’ve heard Ubuntu is a user-friendly distro. Pity if this actually means all sharp toys are locked in a drawer.