Distribute GitLab Community Edition with Spacewalk

GitLab is a very popular alternative to GitHub that is available as free Community Edition for interested hobbyists and smaller companies. For installing the software, there is a script for downloading and installing the particular software packages. If you have a look at the source code of this script, you will see that this script uses conventional
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Short tip: DRBD + EL7: /var/lib/drbd/drbd-minor-0.lkbd: No such file or directory

Recently I stumbled upon the following error message while creating a DRBD volume on CentOS 7: # drbdadm create-md r0 initializing activity log NOT initializing bitmap Writing meta data… lk_bdev_save(/var/lib/drbd/drbd-minor-0.lkbd) failed: No such file or directory New drbd meta data block successfully created. lk_bdev_save(/var/lib/drbd/drbd-minor-0.lkbd) failed: No such file or directory Oops! After executing the command
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Short tip: Please reserve memory by passing “crashkernel=X@Y” parameter to the kernel

While configuring kdump on a system I recently stumbled upon the following error: Please reserve memory by passing “crashkernel=X@Y” parameter to the kernel However, the parameter crashkernel was mentioned in the GRUB configuration file and kernel commandline: $ grep crashkernel /proc/cmdline ro root=/dev/mapper/vg_system-lv_root … crashkernel=auto … rhgb quiet I saw that this setting works for
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Store kernel dumps using kdump on remote machines

If the Linux kernel crashes it is possible to create a memory image (also called vmcore) using a mechanism called kdump. Especially, this is useful if you plan to engage support to fix the reason for the issue. By default, the vmcore is stored under /var/crash. But if the kernel is not able to access
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Spacewalk 2.3 released

After Red Hat Satellite 5.7 was released 3 months ago Spacewalk version 2.3 was published on 14th of april 2015 after 9 months of development. Like the commercial spin-off the recent management suite also offers a more modern web-interface. With version 2.2 this interface’s user experience was overhauled by HTML5, jQuery and Bootstrap. Die updated
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VM Tools for MS-DOS and Windows 3.x

VMware offers software packages including additional applications and drivers for the most support guest operating systems – these packages are also called VMware Tools. Beside recent operating systems also older releases are supported – e.g. there are also Tools for Windows NT. Unfortunately MS-DOS and Windows 3.x are not supported, yet – even if there
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Short tip: VMware vSphere “Module DiskEarly power on failed to lock file”

While booting a virtualized cluster node I stumped upon a suspicious error message recently: Module DiskEarly power on failed to lock file In the VMware forums I found a hint that locking mechanisms might account for this issue. However the thread focussed on desktop products and not on vSphere. I found no lock files (*.lck)
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Short tip: Monitor Koukaam NETIO PDUs with Nagios / Icinga

Koukaam NETIO power outlets offer a network interface that can be used for controlling the particular ports comfortably. It would be even nicer to monitor them with Nagios or Icinga. 2012 I created a provisional bash script for monitoring the ports and time synchronization over NTP. This weekend I migrated the script to Python and
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