Recently I stumbled upon the following error message while creating a DRBD volume on CentOS 7: 1# drbdadm create-md r0 2initializing activity log 3NOT initializing bitmap 4Writing meta data... 5lk_bdev_save(/var/lib/drbd/drbd-minor-0.lkbd) failed: No such file or directory 6New drbd meta data block successfully …

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While configuring kdump on a system I recently stumbled upon the following error: 1Please 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: 1$ grep crashkernel /proc/cmdline 2ro …

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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 the storage …

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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, …

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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 …

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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 …

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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 …

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Because of a recent comment on this blog I stumbled upon an interesting Abandonware webseite. For me this was a reason for diving into a world of forgotten software (thank you very much for the hint, Frank!). While browsing the software archive I vividly recalled my first steps with the computer. Back then - in …

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Last week I had the chance to drive a Mercedes-Benz E class. For me it was the first Mercedes-Benz at all that I drove. Of course I took the opportunity to have a deeper look at the car and summarize my impressions. Technical data The car's basic data looked like this: Model nameE 220 BlueTEC BlueEFFICIENCY EditionType …

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While testing a web application that uses PHP PDO to establish a connection to a PostgreSQL database I stumbled upon the following error message: 1Fatal error: Uncaught exception 'PDOException' with message 'SQLSTATE[08006] [7] FATAL: Ident authentication failed for user "user"' in xxx.php …

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