Category Archives: Linux
Wrong charset for cron
I got a issue on a export job i had that was running daily on which the charset of the data exported wer wrong, and this did not happen when i ran the job manually. I noticed that Cron used … Continue reading
Expanding a kVM disk image
Had to expand a KVM virtual machine today. Luckily, that`s pretty straight forward. You simply create a new disk image with the extra size needed, merge it into the original disk and voila. Then you just need to partition in … Continue reading
Tuning Ubuntu mdadm RAID5/6
If you are using mdadm RAID 5 or 6 with Ubuntu, you might notice that the performance is not all uber all the time. Reason for this is that the default tuning settings for Ubuntu is set to rather motdest … Continue reading
Change hostname on Linode VPS
Linode explains pretty well how to change the hostname of your VPS. But they do not mention that in the latest Ubuntu it is set via Linode`s own DHCP server. So even if you set it via /etc/hostname and in … Continue reading
Clear disk cache on Linux
I have been doing a bit benchmarking in the previous days, and have then needed to clear the disk cache from RAM without wanting to reboot each time. The command i use for that is: 1 sync;echo 3 > /proc/sys/vm/drop_caches … Continue reading
WordPress: Image could not be processed. Please go back and try again.
This is a rather cryptical error message WordPress gives when trying to upload a header image and it fails. The solution is to make sure your server has php(5)-gd installed. Ubuntu: apt-get install php5-gd Red Hat: yum install php-gd
jpackages error: Missing Dependency: /usr/bin/rebuild-security-providers
Jpackages on Red Hat has a nifty bug that causes dependency errors. Luckily, somebody has created a fix as a rpm package wget http://plone.lucidsolutions.co.nz/linux/centos/images/jpackage-utils-compat-el5-0.0.1-1.noarch.rpm rpm -ivh jpackage-utils-compat-el5-0.0.1-1.noarch.rpm And then jpackages works.
ImportError: No module named trac
When working with a new Trac installation you can bump into the error message “ImportError: No module named trac”. This is usually caused by Trac installation not unzipping all the needed files. The following one liner should fix the issue: … Continue reading
package subversion-1.6.12-0.1.el5.rf.x86_64 (which is newer than subversion-1.4.2-4.el5_3.1.i386) is already installed
Package conflict that can appear some times, a simple fix then is to downgrade first, then upgrade: yum –downgrade update subversion yum update subversion
howto: Create a RAID6 with mdadm
Note: This guide discusses RAID6 but the same will work for a RAID5, the only difference is that RAID6 uses two disks for parity data while RAID5 only uses one disk. 1) Make sure that all the hard drives you … Continue reading