Question

Hi,

Our office has a Yeastar S20 VoIP PBX system. However, the pbx does not work behind the RUT950 using pretty much default settings.

Are there changes needed in the settings or is it just not possible?

Regards,

Martijn Henriquez

Answer 1

Hello,

Thank you for contacting us.
Could you provide more information about your issue - what is not working exactly and how it should work?
Also, could you generate a troubleshoot file in a router and provide to me?
Logs in this file could help to find out what cause the issue.

Best regards,

Sigitas K.

Comments

Hi,

The cabled internet in our doctors office can be pretty bad. Therefore I want to provide an internet connection with the RUT950 sim router. 

The office has a local network (LAN) consisting of 5 computers and a PBX system. The computers are connected to a simple switch. The switch and the PBX system are connected to the internet router (using the LAN ports on the router).

When using the RUT950 sim router there is internet on the network and inbound calls can be placed on the PBX system. However, no outbound calls can be placed with the PBX system. 

When using the cabled router (Arris TG3452) there is internet on the network and the PBX system allows for inbound and outbound calls.

The PBX system is provided by the telecom provider Digicel and has 4 SIP lines. The hardware consists of

• - Yeastar S20 (PBX)
• - Unify Switch 8 port UB04 US-8-150W
• - Ubiquiti EdgeRouter ERLite-3
• - Yealink T21P-E2 (PBX phones)

On 20 October 2021 I did a full reset of the RUT950 router and updated the software. It took some fidling but eventually the 4G internet worked. Hereafter, I connected the RUT950 on 26 October 2021 and checked:

• - internet connection on network (YES)
• - inbound calls (YES)
• - outbound calls (NO)

The troubleshoot file is attached through the link below.

Please let me know if any other information is needed.

Regards,

Martijn

troubleshoot file

---

Hello,

Thank you for an informative answer.
Could you try to enable "NAT helpers" for a VoIP protocols and check if that helps?
More information in this link.

Best regards,

Sigitas

---

Hi,

Following up on your advice I enabled the NAT helpers (H323 and SIP). However, the PBX still was not able to place outbound calls.

The troubleshoot file is attached through the link below.

Please let me know if any other information is needed. 

troubleshoot file

Regards,

Martijn

---

Hello,

Please try to upgrade your router's Firmware to latest one RUT9_R_00.07.01.4 without keep setting.

Enter in your router's WebUI, go to System > Firmware:

Uncheck the box of keep all setting.

 Select File as Source of the firmware image.

Click to browse your computer for a firmware image file.

Upload the firmware image to the router and attempts to verify its validity.

Click the Upgrade button to begin the update. More information can be found here

NAT Helpers feature was removed from RUT9 firmware since FW version RUT9_R_00.07.00 (after RUT9_R_00.06.08.5)

Best regards,

 

---

Hi,

We tracked the call and captured the event in a pcap file. See attached.

 

It seems the provider is not responding back with the 180 RINGING packet after 100 Trying on both legs of the call. I'd suggest showing them the packet capture you sent me and ask why the 180 RINGING packets are missing after the 100 Trying. Perhaps there is a wrong credential or maybe they require a different type of authentication for the SIP trunk.

The provider does not respond and I am wondering if you can help me troubleshoot this problem further?

Regards, Martijn

---

> I am wondering if you can help me troubleshoot this problem further?

Yes, but the download link for the pcap you provided doesn't look correct could you check it ?

Answer 2

Hi,

Following up on your advice I upgraded the firmware to RUT9_R_00.07.01.4. 

However, the PBX still was not able to place outbound calls.

The troubleshoot file is attached through the link below.

Please let me know if any other information is needed. 

troubleshoot file

Regards,

Martijn

Comments

Hi,

Yes, sorry. the link is fixed.

pcap

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A diagram of the network would help a lot. From the ip addresses visible in the pcap: 192.168.1.2 192.168.1.232 192.168.1.230 139.168.1.231 192.168.1.232 192.168.1.234 10.33.32.2 10.0.12.4. The pcap comes from the RUT ?

If I am not mistaken, the SIP server at digicel :

1. replies to INVITES without authentication with 401 Unauthorized then the transaction closes with an ACK,
2. but stays completely silent if the INVITE contains credentials and response for the previous challenge ... Strange.

Do you have a way to capture the traffic on port 5060 when using the original cable modem ?

---

Hi,

Below I included the diagram of the network with the RUT sim router which does not allow outbound calls. Note that when the RUT router is replaced by a cabled modem router the problem goes away.

The pcap was from the PBX s20 (not the RUT). 

The RUT also provides a small LAN network in the office consisting of 4 computers and two network printers

When I am accessing a device on the network I use the following 

192.168.1.2  --> PBX s20
192.168.1.232 192.168.1.230 139.168.1.231 192.168.1.234 --> I do not know
10.33.32.2 --> is in the PBX s20 under WAN (see image below)
10.0.12.4. --> I do not know

I can capture the traffic from the s20 using the original cable modem. I provide that next week.

I do not know where port 5060 sits.

Regards, Martijn

---

In addition to a capture when using the cable modem, could you also:

1. show the output of ifconfig on the RUT using a ssh or CLI console,
2. capture an outgoing call on the RUT using tcpdump -i any -n -v -s 0 -w p5060.pcap 'port 5060'