Guides tagged “firewall”
Step-by-step MdmHost guides about firewall, sorted A-Z.
76 guides · page 2 of 4
Find and unblock an IP address in WHM with CSF
Search CSF for a blocked IP, read why LFD blocked it, remove the block in WHM or SSH, and stop the same customer being blocked again.
firewalld zones explained: public, trusted, drop and custom zones
Learn what firewalld zones do, how traffic is matched to a zone by interface or source IP, and how to build a custom admin zone so only your IPs can reach SSH.
First steps after your Linux VPS is ready (SSH, updates, firewall)
Log in over SSH, change the root password, install updates, add a sudo user and switch on a firewall without locking yourself out.
First steps on a new Windows VPS
Connect, change the Administrator password, install updates, check the firewall and plan backups in your first session on a new Windows VPS.
Fix "Remote Desktop can't connect to the remote computer"
Check the server is running, test the RDP port, rule out network blocks and repair Remote Desktop settings from the browser console.
Fix SSH "connection refused", "timed out" and "permission denied"
Work out what each SSH error means, test the port from your computer, and use the control panel's browser console to fix the firewall, the SSH service or key permissions.
Harden a Virtualizor master and its KVM nodes
Secure Virtualizor: restrict admin panel access by IP, enforce 2FA, use SSL, firewall node ports, secure SSH, protect API keys and isolate VPS network traffic.
HestiaCP: manage packages, users and firewall rules
Create a hosting package in HestiaCP, add a user who inherits it, then add and test firewall rules from the panel or the CLI without locking yourself out of SSH.
How to install and configure Imunify360 on a cPanel server (root guide)
Install Imunify360 on a cPanel server with i360deploy.sh, then configure malware scanning, auto-cleanup, Proactive Defense and firewall settings in WHM.
Implementing a Web Application Firewall on Nginx with ModSecurity
Install the ModSecurity module on Nginx, load the OWASP Core Rule Set, run in detection mode first, then block SQL injection and XSS with tuned rules.
Imunify360 command line: essential imunify360-agent commands for root
Use imunify360-agent from SSH to whitelist and unblock IPs, start malware scans, list infected files, clean or restore them and check the agent's status.
Imunify360 firewall settings: ports, country blocking and DoS protection (root guide)
Configure the Imunify360 firewall as root: open and close TCP/UDP ports, block countries, enable DoS protection, and avoid locking out cPanel, mail or SSH.
Imunify360 firewall: blacklist IPs, block countries and manage ports
Use the Imunify360 firewall in WHM to blacklist IPs and subnets, block whole countries, understand the graylist, and open or close ports from the UI or CLI.
Imunify360 firewall: whitelist, blacklist and grey list explained
How the Imunify360 firewall lists work (white, black and grey), when an IP should be whitelisted, how to request it on MdmHost and the risks of whitelisting.
Imunify360 on cPanel hosting: what it protects and how to use it
An overview of Imunify360 on MdmHost: malware scanning, Proactive Defense, the firewall, WAF and WebShield, what you see in cPanel and what MdmHost manages for you.
Imunify360 WebShield and CAPTCHA pages explained
Why visitors sometimes see an Imunify360 CAPTCHA or challenge page, how WebShield and the grey list work, and what to do if real visitors or bots you need are challenged.
Install and configure CSF and LFD firewall on a cPanel/WHM server
Install ConfigServer Security & Firewall (CSF) with LFD on a WHM server, set the essential csf.conf options, take it out of testing mode and manage it from WHM.
Install SQL Server Express on a Windows VPS
Install SQL Server Express and SSMS, create a database and app login, and allow remote connections only from your own IP address.
iptables basics: list, allow, drop and save rules
Learn how iptables chains and rule order work, then build a small ruleset that allows SSH and web traffic, drops everything else and can be edited by line number.
Linux Firewall: Using iptables to Implement Connection Tracking Limits
Cap new and simultaneous connections on a Linux VPS with iptables conntrack, limit, connlimit and hashlimit rules, and size the conntrack table so it does not fill up.
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