Amavis is an open-source content filter solution for electronic mail. It implement mail message transfer, decoding, processing, checking and interfacing with external content filters to provide protection against spam, viruses and other malware. It may be considered an middleware between a mailer (MTA) and one or more content filters. In Read more
VMware vCenter Server is an server management solution which provides a centralised platform for controlling vSphere environments. Snapshots can be used for development and testing purposes. It can be considered as a quick failsafe to be able to rollback before a patch performing tests on certain applications residing on VM. The Read more
While CentOS 7 will reach its EOL in 2024-06-30 users will be required to migrate to CentOS Stream 8 at least. While there is no official option to upgrade to CentOS 9 Stream we will cover today only upgrading from CentOS 7 to CentOS 8 Stream. In this tutorial I Read more
In previous post I’ve discusses how to setup 2FA using Yubikey with any Ubuntu box gnome login. This time we will discuss about how to lock screen when Yubikey will be removed. This is a mandatory security requirement while using Yubikey to complete secure your box. First of all we Read more
With YubiKey you can protects access to computers, networks, and online services. YubiKey 5 Series eliminates account takeovers by providing strong phishing defense using multi-protocol capabilities that can secure legacy and modern systems. It provides a range of authentication choices including strong two-factor, multi-factor and passwordless authentication, and seamless touch-to-sign. Read more
In most cases we can use official Docker images hosted on the public Hub but in some cases there are needed to build custom images. We can add some additional packages to the OS or add everything that is needed with recurence. To build custom images we will use a Read more
Today we will learn to configure out Proxmox hypervisor on a rented server in Hetzner datacenter. Proxmox need a special setup for public IPs because they filter traffic based on MAC address of physical host and a standard bridge is not enough. Also today we will configure a second linux Read more
In this post I will describe steps to replace a failed mirror disk in a software RAID array. As an example we will use /dev/sda1 as good partition, and /dev/sdb1 as failing partition. Before starting it is recommended to backup the original disk. Before removing raid disk, please run the Read more
Configure Strong Ciphers Configure mailbox settings Open file /opt/zimbra/conf/localconfig.xml and find the line mailboxd_java_options and set it like the following one. Configure DH parameters Set additional HTTP headers Validate settings using SSL Labs on url https://www.ssllabs.com/ssltest/analyze.html Looking to secure your email infrastructure and prevent attacks?→ Explore our Emailing Solutions
Kubernetes is a portable, extensible, open-source platform for managing containerized workloads and services, that facilitates both declarative configuration and automation. It has a large, rapidly growing ecosystem. Kubernetes services, support, and tools are widely available. K8s is a nice to have for developers, security researchers but not limited to because Read more