Step-by-step guides and fixes for server administrators: cPanel, DirectAdmin, Windows Server, email, DNS, security and more. Free to read, tested on real servers. Press / to search.
Jump to: Cheat sheets Installation guides Scripts Free tools
Nothing matches. Try a shorter word or another section.
PJSIP Behind NAT: Asterisk and FreePBX Settings for Two-Way Audio
Configure Asterisk PJSIP and FreePBX behind NAT: local_net and external addresses on the transport, rtp_symmetric, force_rport and rewrite_contact on endpoints, router port forwards and SIP ALG, and how to confirm it with the PJSIP logger.
October 3, 2026
fail2ban for Asterisk and FreePBX: Block SIP Password Guessing
Set up fail2ban for Asterisk PJSIP: turn on the security log, confirm the stock filter matches with fail2ban-regex, create a jail that reads the right files, test a ban, and keep your SIP provider and office off the ban list.
October 3, 2026
How Many SIP Channels Do You Need? Size SIP Trunks with Erlang B
Size SIP trunks properly: measure busy-hour traffic from your PBX CDR, convert it to Erlangs, choose channels with Erlang B for a 1% grade of service, then check bandwidth and set the channel limit on the PBX.
October 3, 2026
Troubleshoot SIP Calls with sngrep and the Asterisk PJSIP Logger
How to use sngrep and the Asterisk PJSIP logger to capture a failing call, read the SIP ladder, save a pcap, check RTP audio, and find NAT, codec and authentication problems on Asterisk and FreePBX.
October 3, 2026
SIP Error Codes on Asterisk and FreePBX: Fix 403, 404, 408, 488 and 503
A troubleshooting walk-through for the SIP errors that break calls on Asterisk, FreePBX and SIP trunks: how to find the failing response, then what causes 403, 404, 408, 480, 488 and 503 and how to fix each.
October 3, 2026
Convert Asterisk Call Recordings to MP3 (FreePBX, Issabel)
How to convert Asterisk, FreePBX and Issabel call recordings from WAV, WAV49 and GSM to MP3: one file with ffmpeg or sox, the whole archive with a script, and every new call automatically, without breaking the call log player.
October 3, 2026
Server hacked: incident response runbook for Linux and cPanel Pro
An incident response runbook for a hacked Linux or cPanel server: contain it, preserve evidence, find the entry point, decide clean or rebuild, rotate credentials in the right order and tell customers.
September 30, 2026
MySQL/MariaDB won’t start: crash recovery runbook Pro
When MariaDB won't start after a crash, this runbook reads the error log first, matches the common causes, walks innodb_force_recovery levels 1 to 6 safely, and rebuilds from a dump on cPanel and DirectAdmin.
September 30, 2026
Mail server IP blacklisted: delisting runbook Pro
What to do with a mail server IP blacklisted by Spamhaus, Barracuda or Microsoft: find and stop the source, clean the queue, fix rDNS, SPF, DKIM and DMARC, delist, and relay mail meanwhile.
September 30, 2026
Disk full on a production server: recovery runbook Pro
A recovery runbook for a disk full on a production server: safe space to free first, inode exhaustion, what never to delete, and how to bring MySQL, Exim and Dovecot back cleanly after ENOSPC.
September 30, 2026
WP Toolkit CVE-2026-87900: what is affected and how to patch to 6.11.3
WP Toolkit CVE-2026-87900 is a critical argument-injection flaw in WP Toolkit for cPanel 6.11.2-10794 and earlier. Which versions are affected, how to confirm the fix, and what to check afterwards.
September 30, 2026
File Share Auditing: Find Who Deleted a File in 5 Steps
Turn on file share auditing on a Windows Server 2025 file server so you can answer "who deleted this file?": audit policy, SACLs in the GUI and PowerShell, events 4663 with the DELETE access mask, 4660 and 5145, a search script, log sizing and restoring from Previous Versions.
September 30, 2026