Fixing the Bootloader of a Ubuntu RAID System

Posted on Mon 19 August 2019 in Sysadmin • Tagged with Ubuntu, GRUB, RAID, bootloader, web server

If the remote Ubuntu machine does not boot showing the following error

error: unknown filesystem
 Entering rescue mode...
 grub rescue>

the GRUB bootloader is broken and can be fixed in one of the following ways.

Using the GRUB rescue concole

Follow the steps described in this blog post.

Using a …

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Mounting a Samba Share on the Raspberry Pi

Posted on Fri 07 December 2018 in Sysadmin • Tagged with Raspberry Pi, Samba, Raspbian

Install the following packages:

apt-get install  samba-common smbclient samba-common-bin smbclient  cifs-utils

Create a local directory:

mkdir /mnt/abc

Mount the Samba share using your username:

mount -t cifs //server/share /mnt/abc -o user=uwe

If the Samba share is provided by a FritzBox via its NAS feature and assuming …

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Upgrade Your Apache to a Newer PHP Version

Posted on Fri 08 June 2018 in Sysadmin • Tagged with Nextcloud, PHP, Apache

Upgrading PHP from 7.0 to 7.1 or 7.2 on Ubuntu 16.04 LTS is almost trivial as this blog post (in German) explains:

First, add a PPA (personal package archive):

sudo apt-get install -y python-software-properties (falls nicht bereits installiert)
sudo add-apt-repository -y ppa:ondrej/php
sudo apt-get …

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Setting up a new Ubuntu Webserver

Posted on Sat 11 November 2017 in Sysadmin • Tagged with Ubuntu, webserver

Here's a collection of links that provide helpful information when you have a brandnew Ubuntu machine with root access and you want to set it up as a webserver:

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Setting up a systemd Service under Ubuntu

Posted on Sat 11 November 2017 in Sysadmin • Tagged with Ubuntu, systemd, service

Starting with 15.04, Ubuntu uses systemd instead of Upstart as the default system and service manager. This page offers a good comparison between the two systems.

If you want to add a new systemd service (e.g. for running a Java application everytime your machine boots), create the following …

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Redirecting Requests from Apache to Jetty

Posted on Sun 05 November 2017 in Sysadmin • Tagged with Apache, Jetty, Ubuntu, web server, SSL, proxy

Assuming you are running an Apache server with a virtual host for, put this into the virtual host's .conf file to redirect all traffic to a Jetty web server running locally behind your Apache:

<Proxy *>
    Order deny,allow
    Allow from all

ProxyPass / http://localhost:1234/ retry …

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40 Falsehoods Programmers Believe about Names

Posted on Thu 27 July 2017 in General Software Development • Tagged with names, Patrick McKenzie

Patrick McKenzie has never seen a computer system that handles names properly. Sad!

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Programming as if the Domain (and Performance) Mattered

Posted on Wed 26 July 2017 in General Software Development • Tagged with Carlo Pescio, performance

A long read by my man Carlo Pescio.

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It's not CI, it's just CI Theatre

Posted on Fri 26 May 2017 in General Software Development • Tagged with continuous integration, Suzie Prince, ThoughtWorks

Are you practising CI? Find out by reading this post by Suzie Prince.

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The Initializer Pattern in Java

Posted on Sat 18 March 2017 in Design Patterns • Tagged with builder pattern, Heinz Kabutz, initializer, Java

A "type-safe builder pattern in Java".

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