Setup Details:
• 3CX Version: [Your 3CX Version]
• Hosting: Google Cloud VM
• Firewall: Google Cloud firewall configured to allow SIP/RTP traffic
• FXO Gateway: Yeastar S20 (located at home)
• Local IP: 192.168._._
• Public IP: 41.__.__._
• PSTN Line Type: Analog (FXO)
• Authentication Type: IP-based (no username/password)
• SIP Trunk in 3CX: Configured to use Yeastar’s public IP
Issue Description:
I have a 3CX system hosted on Google Cloud, and I am using a Yeastar S20 FXO Gateway at my home to connect an analog PSTN line to 3CX. However, I keep receiving the following Event Log Warning:
Event ID: 30051
Type: Warning
Unidentified Incoming Call. Review INVITE and adjust source identification.
Upon checking the logs, I can see that the INVITE request is reaching 3CX but is being rejected as an unidentified call.
Troubleshooting Done So Far:
1. Whitelisted Yeastar’s Public IP (41.___.___.__) in 3CX Security Settings (IP Blacklist).
2. Ensured 3CX SIP Trunk is set to IP-based authentication (no username/password).
3. Verified Firewall Rules:
• Google Cloud allows UDP 5060 (SIP) and UDP 10000-20000 (RTP) from Yeastar’s Public IP.
• Home Router forwards SIP/RTP traffic from 192.168._.__._ (Yeastar S20) to 3CX Public IP.
4. Checked SIP Headers in Yeastar S20:
• SIP INVITE contains no Caller ID (FXO line does not provide it).
• Yeastar S20 is sending sip:[email protected]._.__ → <sip:3CX Server>.
5. Set a Default Caller ID in Yeastar S20 to 1000 (to avoid blank Caller ID issues).
6. Enabled “Use Default Number If Missing” in 3CX SIP Trunk Settings.
7. Adjusted SIP Format Settings:
• Yeastar S20 now sends P-Asserted-Identity in SIP headers.
• Changed Caller ID format to National Format (260XXXXXXXXX).
8. Restarted 3CX and Yeastar S20, but still receiving Event ID 30051.
What I Need Help With:
1. How can I make 3CX recognize calls from my Yeastar S20 without rejecting them as “Unidentified”?
2. Is there a way to configure 3CX to accept calls without requiring Caller ID?
3. Should I adjust the SIP headers or change how the INVITE request is formatted?
4. Any additional firewall or SIP trunk settings that might help resolve this issue?
• 3CX Version: [Your 3CX Version]
• Hosting: Google Cloud VM
• Firewall: Google Cloud firewall configured to allow SIP/RTP traffic
• FXO Gateway: Yeastar S20 (located at home)
• Local IP: 192.168._._
• Public IP: 41.__.__._
• PSTN Line Type: Analog (FXO)
• Authentication Type: IP-based (no username/password)
• SIP Trunk in 3CX: Configured to use Yeastar’s public IP
Issue Description:
I have a 3CX system hosted on Google Cloud, and I am using a Yeastar S20 FXO Gateway at my home to connect an analog PSTN line to 3CX. However, I keep receiving the following Event Log Warning:
Event ID: 30051
Type: Warning
Unidentified Incoming Call. Review INVITE and adjust source identification.
Upon checking the logs, I can see that the INVITE request is reaching 3CX but is being rejected as an unidentified call.
Troubleshooting Done So Far:
1. Whitelisted Yeastar’s Public IP (41.___.___.__) in 3CX Security Settings (IP Blacklist).
2. Ensured 3CX SIP Trunk is set to IP-based authentication (no username/password).
3. Verified Firewall Rules:
• Google Cloud allows UDP 5060 (SIP) and UDP 10000-20000 (RTP) from Yeastar’s Public IP.
• Home Router forwards SIP/RTP traffic from 192.168._.__._ (Yeastar S20) to 3CX Public IP.
4. Checked SIP Headers in Yeastar S20:
• SIP INVITE contains no Caller ID (FXO line does not provide it).
• Yeastar S20 is sending sip:[email protected]._.__ → <sip:3CX Server>.
5. Set a Default Caller ID in Yeastar S20 to 1000 (to avoid blank Caller ID issues).
6. Enabled “Use Default Number If Missing” in 3CX SIP Trunk Settings.
7. Adjusted SIP Format Settings:
• Yeastar S20 now sends P-Asserted-Identity in SIP headers.
• Changed Caller ID format to National Format (260XXXXXXXXX).
8. Restarted 3CX and Yeastar S20, but still receiving Event ID 30051.
What I Need Help With:
1. How can I make 3CX recognize calls from my Yeastar S20 without rejecting them as “Unidentified”?
2. Is there a way to configure 3CX to accept calls without requiring Caller ID?
3. Should I adjust the SIP headers or change how the INVITE request is formatted?
4. Any additional firewall or SIP trunk settings that might help resolve this issue?
