SIP registration fails over VLAN (RUTM08) for both Fritz!Box and softphone clients. DNS resolution of ISPvoce.eolo.it returns a private IP , but clients behind LAN cannot resolve or reach it reliably. Tested with ISP DNS and custom redirect; issue persists. Anyone faced similar DNS behavior with SIP? Many thanks.
Hello,
Thank you for your inquiry. Your request is currently under review and analysis. Once the evaluation is complete, I will get back to you with further information, findings, or suggestions.
In the meantime, could you kindly check if the DNS resolution issue persists when using either Google or Cloudflare DNS (8.8.8.8 / 1.1.1.1)? Additionally, could you confirm whether your router is operating behind CGNAT? It would also be helpful if you could share screenshots of the nslookup results you’ve performed. Thank you.
Best regards,
Hello,
Thank you for your reply.
I’ve tested DNS resolution from a client connected behind the RUTM08 (LAN 192.168.1.x).
Google DNS (8.8.8.8) and Cloudflare (1.1.1.1) return NXDOMAIN for voce.eolo.it.
EOLO DNS (88.149.128.12 and 88.149.128.22) correctly resolve voce.eolo.it to 10.40.9.100.
Please find attached the screenshots of the tests.
Also, I confirm the router is operating behind CGNAT (WAN IP differs from public IP seen by external tools).
Best regards,
Good morning,
in case further information are needed I am fully available. Forgot to tell the firmware version of the router is RUTM_R_00.07.16.3.
Many thanks
Hello,
Apologies for the delay.
In this case, to assist and understand your situation effectively, we’ll need to continue this process privately, because sensitive/publicly unshareable information, such as the troubleshoot file, public IP addresses, serial numbers, etc., needs to be collected.
You should find a support request form in the inbox of the email address you used for your forum registration. Kindly fill out the form, and please reference Ticket ID: 15457 when submitting it. Once the form is completed, we’ll contact you directly via email to investigate the issue in detail and help work towards a solution.
Best regards,
Many thanks. done as per your instruction. Regards.
Hello I have sent all the material you’ve requested via email. Just a kind reminder for a follow up. Regards