The previous article about iptables demonstrated how it can be used to secure your system. Recently, a new firewall called FirewallD was introduced by Red Hat Enterprise Linux 7.0 (RHEL). FirewallD is the default firewall for Red Hat/CentOS/Rocky Linux and the SUSE family.
This tutorial will provide you with a basic understanding of FirewallD and the ways to secure your system using the firewall-cmd command.
We often need to check connectivity to troubleshoot network issues, or want to check whether our server is online. We created this article to show you how to do this.
There are many handy Linux tools for this:
Ping is one of the most widely used commands to check whether a server or remote host is up and responding. Ping sends ICMP ECHO_REQUEST to the server.
If ICMP is blocked from the server-side or cloud provider, then the ping command may not work as expected (like AWS ec2 instance).
Here, we assume that cloud providers firewalls do not block ICMP.
No application can be considered completely secure. Majority of them have flaws and weak areas, leaving doors open for security threats. You can opt for various solutions to secure your data. One of the most well-known ways is by using Fail2Ban.
The obvious definition of this application includes monitoring the logs of common services and looking for malicious signs. It scans the log files and automatically bans the IPs with suspicious activity (e.g. a large number of failed login attempts) . These might include exploitations, password failures, etc.
Another Fail2Ban feature is to update the firewall rules. It comes with various filters, including apache, ssh, courier, etc. Each of them serves a different purpose and can be configured.
Now that you know what Fail2Ban is, let’s see how to use Fail2Ban to secure your server. Check this comprehensive Fail2Ban configuration guide:
How to check open ports on a Linux server?
We often have to check open ports on our Linux server to troubleshoot server problems, configure a firewall, and improve our server’s security. There are many third-party tools for this available in the market. In this article we will show you how to use nmap, netstat, ss, and lsof commands to check the open ports and find out the applications associated with those ports.
Many Linux users have used the ifconfig command as a primary tool for obtaining network information. However, this command is obsolete, and we now have the IP command in its place. The IP command has many features compared to the old ifconfig command. Today, you will learn how to use it by practical examples.
MySQL is the most popular Database Management System that has upgraded over time, every upgrade coming with many exciting features. The same refers to MySQL 8.0.
MySQL 8.0 features set is something every developer should be aware of. We created an overall article about the new features of MySQL 8.0 for those, who’ve missed the update or would like to learn more details.
Firewall security with advanced protection
You can easily secure your infrastructure using stateful firewalls at no extra cost. Define inbound and outbound rules to deny unnecessary traffic. Once configured, you can assign as many cloud servers as you need.
Load balancers make it stress-free to scale requests by automatically distributing traffic through your infrastructure. It handles use cases such as ...