SIP Layer Troubleshooting.md - edlentz/Nimbus GitHub Wiki

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📄 SIP-Layer-Troubleshooting.md

# SIP Layer Troubleshooting

## Symptoms
- Phones not registering
- SIP errors: 403, 404, 486
- Call drops after dialing

## Checklist
- Match device credentials with extension
- Confirm transport type:
  - PJSIP → UDP 5300 or 5060
  - Chan_SIP → UDP 5060
- NAT config matches device and FreePBX
- Extension enabled in FreePBX
- Check for fail2ban or IP blacklist

##  Tools
sngrep  --  Visual tool to monitor all sip traffic from the CLI

The following are used in the Admin/Asterisk CLI page from the GUI
sip show peers
pjsip show endpoints
sip set debug on
pjsip set logger on