Configure DomainKeys- DKIM (OpenDKIM) with Postfix on CentOS 7 Rumi, March 31, 2021March 31, 2021 OpenDKIM is method to digitally sign & verify emails on the mail servers using public & private keys. In other words opendkim implements the DKIM (DomainKeys Identified Mail) standard for signing and verifying email messages on a per-domain basis. DomainKeys are implemented to reduce the chances of outgoing mails to… Continue Reading
Ping behind proxy using httping Rumi, March 5, 2021 You can use utility httping for that. It sends a HEAD request (by default) to a web server and measures the time it took to get a response. The utility is available through a number of repositories for different OS’es and Linux distros: Ubuntu: sudo apt install httping Alpine: sudo… Continue Reading
enable SNMP on Xen (XCP-NG) hypervisors Rumi, March 5, 2021 There are six steps to correctly configuring SNMP on your Citrix Xen hypervisor. These steps don’t require a system restart and are non-service affecting. To start, we assume you’re running Xen v6.x or v7.x, and are logged into the Xen CLI as root. 1. Enable the SNMP daemon Enable the… Continue Reading
How to find out the connected interface using linux command Rumi, October 26, 2020 Method 1 To find out the connected state of a network cable in Linux, just run: $ cat /sys/class/net/enp5s0/carrier Sample output: 1 If you got output as “1” (Number one), It means that the network cable is connected with the network card. Also, you can do this with the following command too:… Continue Reading
Install LAMP on CentOS 7 with PHP 5.4/7.0/7.1/7.2/7.3/7.4 Rumi, October 26, 2020 Preliminary Note In this tutorial, I use the hostname server1.example.com with the IP p 192.168.0.100. These settings might differ for you, so you have to replace them where appropriate. I will add the EPEL repo here to install latest phpMyAdmin as follows: rpm –import /etc/pki/rpm-gpg/RPM-GPG-KEY* yum -y install epel-release To edit files on… Continue Reading
Remove Node from Proxmox Cluster Rumi, September 9, 2020 Step 1 : Migrate all VMs to another active node Migrate all VMs to another active node. You can use the live migration feature if you have a shared storage or offline migration if you only have local storage. Step 2 : Display all active nodes Display all active nodes in… Continue Reading
Add Geolocation to Graylog 2 Rumi, August 16, 2020 The Graylog Map Widget is the plugin providing geolocation capabilities to Graylog. The plugin is compatible with Graylog 2.0.0 and higher, and it is installed by default, although some configuration is still required on your side. This section explains how to configure the plugin in detail. In case you need to reinstall the… Continue Reading
Reclaim disk space from a sparse image file qcow2/ vmdk Rumi, July 23, 2020July 23, 2020 Sparse disk image formats such as qcow2 only consume the physical disk space which they need. For example, if a guest is given a qcow2 image with a size of 100GB but has only written to 10GB then only 10GB of physical disk space will be used. There is some… Continue Reading
Install Jitsi Meet and configure load balancing Rumi, July 14, 2020 Jitsi Meet is an open-source (Apache) WebRTC JavaScript application that uses Jitsi Videobridge to provide high quality, secure and scalable video conferences. It can be used as a replacement for proprietary services like Zoom, Whereby, Teams, Skype and many others. Requirements At least two Linux systems with Debian 10 DNS… Continue Reading
Enable authentication of Jitsi Meet Rumi, July 14, 2020July 14, 2020 A basic installation of Jitsi Meet gets you up and running within shortest time, probably in less than 15 minutes. There are hardly any configuration changes necessary. Most important information is a fully qualified domain name (FQDN), and that’s it. However such a default installation of Jitsi Meet is open…. Continue Reading