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
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
Posted in Linux Administration, Virtualisation
Tagged SSH, vagrant, vagrant plugins, vagrant-proxyconf, Virtualbox
Comments Off on Testing environment setup using Vagrant
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
Posted in Linux Administration
Tagged cli, command line, HP, raid, RAID5, smart array
Comments Off on Create hardware raid on HP via hpacucli
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
Posted in Linux Administration
Tagged autofs, LinuxMint, mount, NFS
Comments Off on Linux Mint – Mount an NFS share automatically
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
Posted in Encryption, Security
Tagged authentication, encryption, gnupg, gpg, pgp, signing, subkeys
Comments Off on Create GnuPG key with sub-keys to sign, encrypt, authenticate
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
Posted in Linux Administration, Security
Tagged apt, apt-file, Debian, gnupg, hopenpgp-tools, Linux, LinuxMint, ubuntu
Comments Off on apt – install the package that contains a specific file
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
Posted in Monitoring
Tagged create, graph, rrdtool
Comments Off on Understand the basics of rrdtool to create a simple graph
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
Posted in Encryption, Linux Administration, Security
Tagged cryptsetup, encryption, luks, parted, partitioning, resize
Comments Off on Increase the size of a LUKS encrypted partition
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
Posted in PHP, Web technologies
Tagged CentOS, PHP, yum
Comments Off on Update to PHP 5.6 on CentOS 6 using remi repository
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
Posted in Linux Administration, Mailserver
Tagged check_sender_access, email, postfix, recipient_restrictions, reject, sender address, sender_access
Comments Off on Permanently reject a specific email sender address using postfix
