We use ConfigServer Firewall (CSF) in many of our VPS and dedicated servers to easily manage firewall services.
CSF uses a login failure Daemon (LFD) to track large number of failed login attempts based on IP address to the server by watching logs. If more than a certain number of login failures happens from a particular IP address, the IP will be blocked temporarily and eventually permanently if it continues.
If you want to find the reason behind the IP block, you can use the below command after accessing the server via ssh:
csf -g x.x.x.x
replace x.x.x.x with your IP address you need to remove the IP block.
After the IP address is blocked, the individual connecting from that IP address will not be allowed to access to any of the services. Sometimes IP blocks happens false-positively and therefore you must remove some IP blocks. The best thing we can do here is run the below command:
csf -dr x.x.x.x
replace x.x.x.x with your IP address you need to remove the IP block.
If you want to temporarily allow an IP address, you need to run the following command:
csf -ta x.x.x.x 2d
Here, 2d means the IP will be temporarily allowed for two days. replace x.x.x.x with your IP address you need to remove the IP block.
If the IP is blocked temporarily you have to run the below command:
csf -tr x.x.x.x
replace x.x.x.x with your IP address you need to remove the IP block.
You have to restart CSF using the below command for the change to take effect
csf -r
You can also perform this action directly from the WHM interface. Please follow the steps below:
Log in to WHM. If you're not sure how, you can follow this guide.
Once you've accessed WHM, search for ConfigServer Security & Firewall and click on it.
On the next page, scroll down slightly until you see the Search for IP option. Enter your public IP there and click on it.
On the next page, you'll see details about why the IP was blacklisted. Clicking on Remove IP Block will unblock your public IP from the blacklist.
On the next page, it will confirm that the IP has been whitelisted.
Congratulations! You’ve successfully unblocked IPs from CSF for both Dedicated and Virtual Private Servers.
If you have any questions, please don’t hesitate to contact our team via live chat.
For technical inquiries, please feel free to reach our support team by emailing support@bigscoots.com from your registered email or by submitting a support ticket.