Debugging case for OLT and ONU problem series (i)

Debugging case for OLT and ONU problem

Debugging case for OLT and ONU problem

  Welcome to join our FOT FTTH Blog, enjoy your fiber or telecom equipment debugging and studying case series posts here!

OLT and ONU problem

  We’re having some trouble with several ONUs, but we couldn’t determine a pattern, I mean, it happens on any OLT and on any ONU with any chipset manufacturer.
  The issue is that the customer behind a “faulty” ONU it seems not to receive traffic from the OLT side, but we do can see traffic coming from the customer. I attached a capture where you can see a client with IP *.*.*.43 making an ARP request for its gateway, in this case *.*.*.1, and you can see also the reply, which doesn’t reach the customer so it continue asking.
The following is what we found out:
  The device connected to the Ethernet port of the ONU, can ping the IP, so there is connectivity there.
  Reboot the ONU, from software or doing a power cycle unplugging the power adapter, doesn’t fix the problem.
  If we run for example “interface onu 1/3/1” -> “restore onu” on the OLT, solves the issue.

These are our software version:

OLT Hardware Version : ***************01
OLT Boot Software Version : *******************11
OLT Firmware Version : *******************13
OLT Application Software Version : *******91
Switch Version : Managed(stackable) dev-build: root@localhost.localdomain 201*-09-15 06:11:52 +08

ONU Firmware and Software Version: **42

Please let me know any other info you might need.

The way how to debug (first phase)

Does the ONU had connect another OLT before?
  We also found that when the ONU(C242) connect to one OLT working, and then change to another OLT, not working. Even you power off/on the onu. Need to restore the ONU, and then working. Case the onu save the previous OLT information.
  If you face this problem, you can following the way to fix:
1.use the onu RST button to restore. Press the RST button over 5 seconds, until the onu auto reboot.
2.login the onu web , restore onu.
3. “restore onu” on the OLT, if the OLT support this function.

Latest Blog

About Us

Why FTTH can save telecom cost

FTTH: saving money

【Our Goal】

Benefits our customers via Fiber Network (FTTH).

【FOT Telecom】

Your reliable fiber network equipment and service provider: Read More

Contact us

Email: Skype: fanny-lee2007Tel: +86-20-2209 8370
Add.:97th Science Avenue, Science Town,  Guangzhou, Guangdong, China