How to Stop and Disable Firewalld on CentOS 7

Firewalld is a complete firewall solution that has been made available by default on all CentOS 7 servers, including Liquid Web Core Managed CentOS 7, and Liquid Web Self Managed CentOS 7. On occasion, perhaps for testing, disabling or stopping firewalld may be necessary. Follow the instructions below to disable firewalld and stop firewalld.

It is highly recommended that you have another firewall protecting your network or server before, or immediately after, disabling firewalld.

Pre-Flight Check

  • These instructions are intended specifically for stopping and disabling firewalld CentOS 7.
  • I’ll be working from a Liquid Web Self Managed CentOS 7 server, and I’ll be logged in as root.

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How To Unblock an IP Address in APF

Advanced Policy Firewall, or APF, is a software firewall commonly installed on Liquid Web servers. It is an interface to iptables, which is standard software for managing network ports on Linux. Interacting with iptables can be complex, but APF greatly simplifies the process. APF is only accessible via ssh, and there is no way to make changes in APF through WHM or cPanel.

Pre-Flight Check
  • These instructions are intended specifically for unblocking an IP Address in APF.
  • I’ll be working from a Liquid Web Core Managed CentOS 6.5 server, and I’ll be logged in as root.
  • For further details, see our in-depth look at the APF firewall.
Check APF for Your IP Address

Let’s say that you want to check whether or not a specific IP address, maybe 8.8.8.8 , is blocked by APF. That’s easy!

grep 8.8.8.8 /etc/apf/*

You may receive a result similar to:

/etc/apf/deny_hosts.rules:# added 8.8.8.8 on 04/25/14 13:42:01 with comment: {bfd.courier}
/etc/apf/deny_hosts.rules:8.8.8.8

The above means that BFD detected a brute force attack from the IP 8.8.8.8 on port 25, and automatically added a rule to APF to prevent future connections specifically from that IP address.

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How To Unblock an IP Address in CSF

CSF is generally considered an advanced firewall given it has many more configuration options than most other software firewalls (such as APF). It’s also still simple enough to install and configure, even for novice system administrators. For a simple overview on how to install and configure CSF and its security plugin LFD (Login Failure Daemon), visit our tutorial.

Check CSF for Your IP Address

Let’s say that you want to check whether or not a specific IP address, maybe 8.8.8.8 , is blocked by CSF. That’s easy!

csf -g 8.8.8.8

Continue reading “How To Unblock an IP Address in CSF”

CSF: Config Server Firewall Installation

An alternative firewall to APF is the Config Server Firewall, or CSF.

CSF is generally considered a more advanced firewall as there are more configuration options compared to other firewalls, while still being simple enough to install and configure that even novice administrators can use it. This article will give you a simple overview about how to install and configure CSF and its security plugin LFD (Login Failure Daemon).

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APF Firewall

Advanced Policy Firewall, or APF, is a firewall sometimes seen on Liquid Web’s servers. It is basically an interface to iptables, which is the standard interface to managing network ports on Linux machines. Interacting with iptables can be complex and error-prone, and APF greatly simplifies working with it. However, APF is still only accessible by ssh. There is no way to make changes in APF through WHM or cPanel.

Continue reading “APF Firewall”