You can use Wireguard to connect branch office LANs with a site-to-site VPN. In this article, we will set up a site-to-site VPN using Wireguard and configure routing between networks using an rpm-based distro (RHEL/CentOS/Oracle/Rocky Linux).
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Some administrators use sed or regular expressions to replace variable values in structured files (JSON or YAML). This doesn’t always give a good result. It is much easier to use the jq or yq tools to process structured files.
Continue reading “How to Replace Variable Value in JSON or YAML File?”
In this article, we will show some options for backing up virtual machines on a KVM hypervisor, as well as recovery scenarios. I would like to note that there are no convenient backup tools for KVM, and every administrator uses their own methods and scripts. There are two backup scenarios in KVM: when a VM is stopped (the easiest one, but rarely used) and without stopping the virtual machine.
In this article, we’ll look at how to create a VPN connection from the Linux terminal console and connect to a remote VPN server from the command line. Consider how to create L2TP, PPTP, OpenVPN, and SSTP VPN connections on Linux.
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When trying to connect a copied or moved disk image file (*.VHD/*.VDI) of an Oracle VirtualBox virtual machine, you will receive an error:
VirtualBox - Error
Failed to open the hard disk image file FilePath.vhd.
Cannot register the hard disk FilePath.vhd <GUID> because a hard disk DifferentFilePath.vhd with UUID <GUID> already exists.
Result Code: E_INVALIDARG (0x80070057)
Component: VirtualBoxWrap
Interface:IVirtualBox {GUID}
Callee RC: VBOX_E_OBJECT_NOT_FOUND (0x80BB0001)
Continue reading “VirtualBox: Cannot Register the Hard Disk Already Exists”
Postfix mail server is available in almost all Linux distributions. You can use it as a simple relay (smart host) to send email messages from your local network to user mailboxes and forward email queues to SMTP servers outside your organization. In this article, we’ll show you how to set up an SMTP relay for Microsoft 365 (Office 365, Exchange Online) with postfix on Linux (using Ubuntu/Debian as an example).
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In this article, we’ll look at how to protect the Linux GRUB2 bootloader configuration with a password.
To automate docker partition backups, I recommend using Docker-volume-backup image (https://github.com/offen/docker-volume-backup). This lightweight image (about 15 MB) allows you to connect to any volume in docker and backup files to a local directory, S3-compatible storage (AWS S3, MimIO, Ceph, etc.), or send save it to a remote device via WebDAV or SSH.
Zabbix proxy is one of the infrastructure components that allows you to collect monitoring data from multiple devices and send data to the Zabbix Server. Zabbix Proxy can be used to collect monitoring data from remote locations, from hosts behind a firewall, or to reduce the load on the central Zabbix Server in large environments.
Continue reading “Install and Configure Zabbix Proxy on Linux”
An up-to-date Zabbix Server backup will allow you to quickly restore the monitoring system configuration in case of software failures or hardware failures.
