NBN FTTP gets disconnected and reconnected intermittently (ppp3 LCP down)

[jasonxiec137]

Hi there

My NBN 100 FTTP with TPG provided VX420-G2v modem gets disconnected and reconnected intermittently for a long time, few times per week. I have reached out to TPG Support on call before but no connection issue was identified at that time. So I retrieved the log file from the tp-link VX420-G2v modem and filtered the severity level (severer than Notice) as can be seen in the attached screenshots.

Moreover, I didn't request disconnection or reconnection from my end, the intermittent disconnection issues (it disconnects and reconnects in few minutes but causes internet down) are annoying and significantly undermined the overall experience as NBN 100 plan (FTTP) is supposed to be reliable with minimal down time. Kindly request assistance to troubleshoot further.

The following is a part of the log file recorded when the error was occurring:

2022-09-01 01:41:58 [3] PPP: ppp3 User request
2022-09-01 01:41:58 [3] PPP: ppp3 LCP down
2022-09-01 01:41:58 [4] PPP: ppp3 LCP down
2022-09-01 01:41:59 [3] PPP: ppp3 User request
2022-09-01 01:42:00 [3] PPP: ppp3 User request
2022-09-01 01:42:01 [3] PPP: ppp3 User request
2022-09-01 01:42:02 [3] PPP: ppp3 User request
2022-09-01 01:42:03 [3] PPP: ppp3 User request
2022-09-01 01:42:04 [3] PPP: ppp3

2022-09-01 01:42:16 [3] PPP: ppp2
2022-09-01 01:42:16 [3] PPP: ppp3
2022-09-01 01:42:41 [3] PPP: ppp3 Timeout waiting for PADO packets
2022-09-01 01:42:41 [3] PPP: ppp3
2022-09-01 01:42:42 [3] PPP: ppp2 Timeout waiting for PADO packets
2022-09-01 01:42:42 [3] PPP: ppp2
2022-09-01 01:43:01 [3] PPP: ppp3 Timeout waiting for PADO packets
2022-09-01 01:43:01 [3] PPP: ppp3
2022-09-01 01:43:02 [3] PPP: ppp2 Timeout waiting for PADO packets
2022-09-01 01:43:02 [3] PPP: ppp2
2022-09-01 01:43:03 [3] PPP: ppp2

2022-09-05 10:17:36 [3] PPP: ppp3 User request
2022-09-05 10:17:36 [3] PPP: ppp3 LCP down
2022-09-05 10:17:36 [4] PPP: ppp3 LCP down
2022-09-05 10:17:36 [3] PPP: ppp3

2022-09-06 02:20:05 [3] PPP: ppp3 User request
2022-09-06 02:20:05 [3] PPP: ppp3 LCP down
2022-09-06 02:20:05 [4] PPP: ppp3 LCP down

Kind regards

Jason

[Rica_R]

Let's take a look at your account and check your connectivity issues, @jasonxiec137.

Send us a PM with your TPG account username or customer ID and let us see what's causing the dropout.

Here is how to send us a PM - 
https://community.tpg.com.au/t5/Welcome/How-do-I-private-message-PM-in-the-community/m-p/4093/highli...
 

[jasonxiec137]

Hi there

To document the troubleshooting process and track this PPP LCP down "flash dropout" issue on TPG NBN plan, the up-to-date summary is as follows:

After above post, TPG support stated, "we can't detect any issues on the line after running some tests" by reaching out via private message.

I then performed factory reset on TPG-provided modem VX420-G2v (Firmware Version:2.0.0 0.9 v603c.0 Build 210926 Rel.15288n) as suggested, while I have been receiving the same error (above dropout events and the same log messages) in the past week, reaching about daily basis, which is not expected. I requested a modem replacement accordingly, but I still suspect the issue seems related to the ISP side.

After researching, I notice a similar issue posted in June 2022:

https://community.tpg.com.au/t5/Broadband-Internet/ppp3-LCP-down/m-p/115056

[BasilDV]

Hi @jasonxiec137

I've responded to your private message.

We'll try the replacement first in order to rule out the possible device issue.

We'll be waiting for your response to my PM.

BasilDV

[jasonxiec137]

To document the troubleshooting process, the up-to-date summary is as follows:

I received the replacement modem (Hardware Version:VX420-G2h v2 0) in 26th Sep and have been testing with it, but the same dropout issue occured after 3 days (since first connect) and the logs are listed as follows (filtered severity level above [4] warning):

2016-01-01 10:01:26 [3] PPP: ppp2
2022-10-03 18:02:59 [3] PPP: ppp3 Peer not responding
2022-10-03 18:03:00 [3] PPP: ppp3 LCP down
2022-10-03 18:03:06 [3] PPP: ppp3
2022-10-03 18:03:26 [3] PPP: ppp2 Timeout waiting for PADO packets
2022-10-03 18:03:26 [3] PPP: ppp2
2022-10-03 18:03:46 [3] PPP: ppp2 Timeout waiting for PADO packets
2022-10-03 18:03:46 [3] PPP: ppp2
2022-10-03 18:03:56 [3] PPP: ppp3 Timeout waiting for PADO packets
2022-10-03 18:03:56 [3] PPP: ppp3
2022-10-03 18:04:07 [3] PPP: ppp2 Timeout waiting for PADO packets
2022-10-03 18:04:07 [3] PPP: ppp2
2022-10-03 18:04:16 [3] PPP: ppp3 Timeout waiting for PADO packets
2022-10-03 18:04:16 [3] PPP: ppp3
2022-10-03 18:04:27 [3] PPP: ppp2 Timeout waiting for PADO packets
2022-10-03 18:04:27 [3] PPP: ppp2
2022-10-03 18:04:28 [3] PPP: ppp2
2022-10-03 18:04:36 [3] PPP: ppp3 Timeout waiting for PADO packets
2022-10-03 18:04:36 [3] PPP: ppp3
2022-10-03 18:04:40 [3] PPP: ppp3
2022-10-03 18:05:00 [3] PPP: ppp3 Timeout waiting for PADO packets
2022-10-03 18:05:00 [3] PPP: ppp3
2022-10-03 18:05:01 [3] PPP: ppp2 Timeout waiting for PADO packets
2022-10-03 18:05:01 [3] PPP: ppp2
2022-10-03 18:05:18 [3] PPP: ppp2
2022-10-03 18:05:18 [3] PPP: ppp3
2022-10-03 18:05:44 [3] PPP: ppp3 Timeout waiting for PADO packets
2022-10-03 18:05:44 [3] PPP: ppp3
2022-10-03 18:05:44 [3] PPP: ppp2 Timeout waiting for PADO packets
2022-10-03 18:05:44 [3] PPP: ppp2
2022-10-03 18:05:45 [3] PPP: ppp2

[jasonxiec137]

Update:

The issue has not been resolved after the technician visit (2022-10-20), the tchnician claimed this might be related to an authentication issue and was resolved onsite but it seems not the case (issue still persists). I checked the modem log today and confirmed the LCP down issue occurred twice today as shown in the attached screenshot (1st one from 2022-10-25 03:10:25 to 2022-10-25 03:24:11 and 2nd one around 2022-10-25 19:03:55 GMT+10h).

To address the root cause, can you identify any indicative errors during above down periods for my connection? Is it a known issue with TPG-provided modem hardware or software? Have you received any similar cases with the same symptoms (intermitent connection dropout with PPP LCP down error on modem), how are they resolved?

screent of logs (filtered for warning level):

[BasilDV]

Hi @jasonxiec137

We can't detect any issues within the network with our initial test.

We'd like to arrange another call from our Tech team to check on this further.

Shoot me a PM with your preferred time and best number to be contacted today.

BasilDV

[jasonxiec137]

Hi TPG

I just relocated to a new apartment with TPG FTTH service exclusively, the same "PPP LCP down" log content appeared again (with short dropout, using a new modem from TPG), which makes me suspect whether this is related to TCP's dynamic IP address policy?

The same "PPP LCP down" would cause internet disconnect and reconnect in few minutes with a new IP address, this happened on 2022-12-26 and 2022-12-30 (day time). Please assist on this as it significantly affects my availability when WFH.

[Shane]

Hi @jasonxiec137,

Let us help check the status of the connection. Could you shoot us a PM with your details to proceed with the initial assessment.

How to send a PM? 

Regards,

Hi TPG

I just relocated to a new apartment with TPG FTTH service exclusively, the same "PPP LCP down" log content appeared again (with short dropout, using a new modem from TPG), which makes me suspect whether this is related to TCP's dynamic IP address policy?

The same "PPP LCP down" would cause internet disconnect and reconnect in few minutes with a new IP address, this happened on 2022-12-26 and 2022-12-30 (day time). Please assist on this as it significantly affects my availability when WFH.
 

[themurrayhall]

@jasonxiec137Was this ever resolved? I've been having the same issue for months now.

A tech recomened we buy a new modem, but couldn't garuentee that it would fix it, which is too expennsive an investment for us if there's no guarantee that it'll work.