Networking & Security
Configure IPs, ports, and firewall rules.
By Andy Wallace and 2 others3 authors10 articles
- Add extra IPv4 addresses to your VPSLearn how to add, remove, and persist additional IPv4 addresses on Linux and Windows VPS.
- Fix PuTTY “Connection timed out” when noVNC worksLearn why SSH times out even though noVNC works, and how to restore access step by step.
- Check which ports are open on your VPS firewallSee how to identify open, closed, or filtered ports across both the cloud firewall and your VPS OS firewall.
- Install a free SSL certificate on your VPSLearn how to install and auto-renew a free Let's Encrypt SSL on your VPS using Certbot.
- Enable and troubleshoot port 25 on multiple VPS IPsLearn how to enable SMTP on all assigned IPs, fix routing and firewall issues, and bind your mail server correctly.
- Enable the firewall for your VPSLearn how to enable the firewall and create inbound or outbound rules for your VPS.
- Firewall rule orderLearn how firewall rule position affects traffic filtering and why rule order matters for inbound traffic control.
- Common firewall rules for a VPSExamples of common firewall rules that help secure a VPS without blocking essential access.
- SMTP port 25 unblock requirementsRequest access to SMTP port 25 for outbound email from your VPS after meeting eligibility checks.
- Changing a VPS primary IPUnderstand primary IPv4 changes and additional IP rules.