Mount raw image of entire disc

Raw disc images are very common, they include things like images created using dd for backups and virtual machine disk images. To access the disc image content means the disk image needs to be mounted. Images from a partition can … Continue reading

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Testing environment setup using Vagrant

Setting up a test environment with many different operating systems and versions can be a time consuming task. Installing the different operating systems and configuring them for tests or development can take up a lot of time. Vagrant makes this … Continue reading

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Create hardware raid on HP via hpacucli

Configuring a new hardware raid on a HP server can be done comfortably from the Linux command line without restarting the server. HP provides a small command line tool for this job. The following shows how this tool can be … Continue reading

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Linux Mint – Mount an NFS share automatically

Linux Mint comes pre-installed with all components to mount Windows File sharing (SMB/CIFS) but does not support NFS out of the box. The following post will explain how to enable Linux Mint to mount a NFS share. Additionally the NFS … Continue reading

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Create GnuPG key with sub-keys to sign, encrypt, authenticate

In order to use a GnuPG key on a smartcard or Yubikey, a GnuPG key needs to be created. This post will show you how to create a GnuPG key with sub-keys for signing, encryption and authentication. The authentication key can … Continue reading

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apt – install the package that contains a specific file

Sometimes a command that you execute complains about a dependency being missing on the system. From the file name in the error message it is often not possible to know exactly which package needs to be installed to resolve the … Continue reading

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Understand the basics of rrdtool to create a simple graph

rrdtool is a powerful tool to store time series data and create graphs. It is very easy to create your first simple graph. This how-to will show the quickest way to generating your first graphs while explaining the options used. rrdtool is used in … Continue reading

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Increase the size of a LUKS encrypted partition

Even encrypted discs or partitions sometimes need to have their size increased. A LUKS encrypted volume consists of different layers which all need to be resized. To resize an encrypted volume, multiple steps have to be performed to use the additional … Continue reading

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Update to PHP 5.6 on CentOS 6 using remi repository

With CentOS being a conservative distribution, security patches are still applied to CentOS 6, but no new versions are available. When running some websites – like Virtualmin – on CentOS 6, the old PHP version 5.3.3 can cause problems. Updating to a newer … Continue reading

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Permanently reject a specific email sender address using postfix

Postfix generally accepts all sender addresses. It might be needed in some rare cases to reject one sender addresses for some reason. With postfix, there is the possibility to use the “check_sender_access” to set individual actions per sender address. For the … Continue reading

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