SIP Firewall Rules Generator: iptables, nftables, UFW, firewalld, CSF and pfSense
Generate firewall rules for Asterisk, FreePBX and other SIP servers: SIP limited to your provider and phones, the RTP range open, scanner protection, and the matching rtp.conf and PJSIP NAT settings.
October 3, 2026
SIP Ports Firewall Rules: 4 Setups for CSF, firewalld and pfSense
Which ports a PBX really needs (SIP 5060/5061 and the RTP media range), how to open them in CSF, firewalld and pfSense, and how to restrict SIP to your trunk provider so scanners cannot brute-force extensions.
September 30, 2026
IP Subnet Calculator (IPv4 CIDR)
Visual IPv4 subnet calculator: enter an address with a prefix or mask to see the network, broadcast, usable host range, masks, a bit-by-bit view, where the subnet sits in its parent block and how to split it.
September 29, 2026
TCP Ping (Port 80/443 Latency)
Measure connection time to a host on port 443 or 80 with four TCP handshakes — works even where ICMP ping is blocked by firewalls.
September 29, 2026
What Is My IP Address?
See your public IP address as servers see it, with reverse DNS, network owner and country — useful for firewall whitelisting in CSF, cPHulk, Imunify360 or cloud security groups.
September 29, 2026
IPv6 Subnet Calculator
Expand and compress IPv6 addresses, find the network, first and last address of any prefix, count /64 subnets and build the ip6.arpa PTR name.
September 29, 2026
VPN MTU Fragmentation: Fixes for Slow VPN Throughput
Find the real path MTU with ping and tracepath, spot ICMP black holes and PMTUD failures, set the right MTU and MSS clamping on WireGuard, OpenVPN and IPsec tunnels on Linux and pfSense, and measure the throughput gain with iperf3.
September 29, 2026
Set up a site-to-site WireGuard VPN between pfSense and OPNsense
Build a routed site-to-site WireGuard tunnel between a pfSense CE 2.9 firewall and an OPNsense 26.7 firewall, including key exchange, allowed IPs, interface assignment, static routes, firewall rules and a handshake check.
September 29, 2026
Install OPNsense 26.7 and set up basic firewall and NAT rules
Install OPNsense 26.7 from the DVD or VGA image, assign WAN and LAN, complete the setup wizard, then build sane firewall rules, an outbound NAT policy and a port forward, and verify the result from both sides of the firewall.
September 29, 2026
Install pfSense CE 2.9 step by step with the network installer and ZFS
Walk through the pfSense CE 2.9.0 network installer from boot media to first WebGUI login, choosing WAN and LAN interfaces, ZFS on GPT, the stable branch and the advanced options that matter for a production firewall.
September 29, 2026
pfSense HAProxy with Let’s Encrypt: Reverse Proxy Setup
Publish several internal web applications behind one public IP on pfSense CE 2.9 using the HAProxy package for SNI-based routing and the ACME package for automatic Let's Encrypt certificates, with verification and renewal checks.
September 29, 2026
pfBlockerNG DNS and IP Blocking on pfSense: 2026 Setup
Install pfBlockerNG-devel on pfSense CE 2.9, run the wizard, enable DNSBL with Unbound for ad and malware domain blocking, add GeoIP and threat-feed IP lists, and confirm blocks with the reports and log pages.
September 29, 2026