Guides tagged “firewall”
Step-by-step MdmHost guides about firewall, sorted A-Z.
91 guides · page 2 of 5
cPanel, WHM and Webmail ports explained: 2082/2083, 2086/2087, 2095/2096
What each cPanel service port does, why every service has a plain and an SSL port, how proxy subdomains replace them, and what to do when your network blocks them.
DDoS protection basics for websites and servers
Understand what a DDoS attack is, the difference between network floods and application-layer attacks, and the practical steps that keep a hosted site or VPS online.
Delete, insert and reorder UFW rules safely
List UFW rules by number, delete them by number or by rule text, insert a rule at a set position and reset UFW without cutting off your own SSH session.
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 a Virtualizor slave server that shows offline
Troubleshoot Virtualizor master-to-slave connection problems: check network and ports, the slave service, API key, licence status, disk space and recent firewall changes.
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.
Fix SSH errors: connection refused, timed out and permission denied
Diagnose why you cannot SSH into a server: connection refused, timeouts, host key warnings and permission denied, with the exact checks and fixes for each.
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 fix Cloudflare Error 521: Web server is down
Cloudflare Error 521 means Cloudflare could not open a connection to your origin server. Find out whether the server is down or blocking Cloudflare, and how to fix it.
How to fix ERR_CONNECTION_REFUSED
ERR_CONNECTION_REFUSED means your browser reached the server address but nothing accepted the connection. Learn how to tell a local problem from a server one and fix it.
How to fix ERR_CONNECTION_RESET
ERR_CONNECTION_RESET means the connection was cut off mid-way. Find out how firewalls, proxies, MTU problems and server limits cause it, and the fixes for visitors and site owners.
How to fix ERR_CONNECTION_TIMED_OUT
ERR_CONNECTION_TIMED_OUT means your browser got no answer from the server at all. Learn how firewall blocks, wrong DNS, overloaded servers and local networks cause it.
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.
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