Question

Hello,

> The TBR140 rejects (or incorrectly interprets) the preamble frames of my equipment with more than 56 bits sometimes 58 (yet conforming to the standard).but TRB140 don't works at each time. 

The insertion of an intermediate switch allows a permanent correct dialog.
because the switch works at the ethernet level, so it plays on the preamble of the Ethernet frames by putting them at 7 bytes=56 bits,

> In your opinion, is there a solution to avoid the insertion of the switch (TRB version soft or script)

Answer 1

Hello, this is Martín, Tech Support Engineer from Teltonika Networks.

I have reviewed your issue and it will be forwarded to RnD.
They will need the troubleshoot file of your device after the issue occurs, so can you please attach it to your main question?

Best regards.

Comments

I'm sorry but I don't know how to recover this file.
it was the manufacturer of my equipment who gave me the explanation, the preamble frame is sometimes 8 bytes long

how can we recover this file because I can very easily reproduce the defect

---

This troubleshoot file can be obtained if you head to System → Administration → Troubleshoot on your web interface, and then click on the Download button.

Please keep in mind to produce the file only after you have reproduced the issue, so we have the logs that show what happened.

---

I did the test all night since 15:36 UT on 03/21 and I uploaded the troubleshoot file.

I confirm that the problem only occurs when my equipment is connected directly to the TRB140, if I insert a switch between them it works perfectly.

---

Hello, I apologize for the delay.

I have sent you a private message containing a custom Firmware to address the issue you are experiencing. Any feedback will be appreciated.

Best regards.

---

Hello, first of all thank you for your answer, no problem for the delay it is better late than never.

Unfortunately this version of software does not solve my problem which is exclusively linked to the specificities of my acquisition unit connected to the TBR140, this equipment works on isolated sites supplied with 12v .

For information, the preamble is not 8 bytes but 58 bits.

I think I will buy a 12V powered switch to solve my PB.

In parallel I bought a RUT240 to check if the fact that it has 2 Ethernet ports makes it behave like a switch?

If not, would you have a product from your catalog to suggest to me?

Best regards

---

Hello, and thank you for your feedback.

We received an answer from our developers about this current issue, and they said that unfortunately there is no way to configure our hardware at a bit level to handle Ethernet frames. It's hardware dependent, so, some hardware will handle it while others won't.

Answering your question, the RUT240 interfaces logically work as a switch between it's two interfaces (when it's enabled for WAN to LAN), however, we cannot confirm or deny it is going to work the scenario you are describing as it is specific for your equipment.

For this case, if you need a Switch, you can check our device TSW100, which is a Gigabit switch with five ports, and four of them are PoE.

I'll keep an eye out for any following answers on this issue.
Best regards.