BSNL FTTH Pune users

How's the optical power levels? @vishalrao

Yeah it's not that. Those are normal as before always when it was working fine - optical input power is currently -25 dBm and my modem specs say it support down to -27 dBm

Then its most likely some sort of wiring/OLT issue as you mentioned.

This won't help with the issue as such, but I use this method to monitor the status of the connection.

Whenever the connection goes down/up, a message is pushed to Cron Monitoring - Get Alerts When Your Cron Jobs Fail | Healthchecks.io with the fibre signal status, uptime of the device etc. This however requires you to have backup link for this message to actually go through.

The first screenshot shows the repeated disconnections that I had mentioned the other day in this thread.







The full text of the message is something like below

Yeah fingers crossed it's some issue other than with my ONT 😀 and it gets resolved ASAP.

And I'm too old and lazy these days to do this kind of alerting mechanism even though I have Netgear R7000 router which I guess can be flashed with custom firmware like OpenWRT where all this stuff can be automated?

😀 Yeah, but looks like Netgear R7000 has limited support for OpenWRT. DDWRT seem to be supported though. Personally, I like OpenWRT better, much more customisable than OpenWRT.

Yeah, its a bit of a hack initially, but once its all done, the extra data and alerting could be useful.

Btw even I lose the fibre signal every other day at some point, although not as frequent as you describe. I considered it as the LCO's equipment being restarted or some power failure or something like that. And it usually comes back in like 2-3 minutes. 🤷‍♂️

Dang, it seems to be my ONT is behaving erratically by rebooting every few minutes, would not last more than 20-30 minutes at a go.

I realised it has been powered on and running 24x7 for the last 6-8 months so I switched it off last evening for an hour and then started it again and it was stable for couple of hours.

I again switched it off overnight and today morning also it has been running fine and stable for a couple of hours so far. Will leave it on now and see when it starts misbehaving again.

This now leads me to believe that for past 8-9 months since I got this BSNL FTTH connection I have been facing occasional disconnections and maybe it was my defective modem all along and I have been mistakenly attributing it as BSNL server/OLT problems everytime when the fault probably was with my modem itself 😀

Will try to get it replaced under warranty and also maybe purchase another ONT to compare while using it.

So it seems my Digisol ONT is rebooting regularly only when my router is connected to it! If I directly connect my PC then it is stable for long duration 😀 Tried changing ethernet cables, factory reset and reconfigure of both ONT and router, tried a different router too, no luck.

So will have to get my ONT replaced under warranty (still 2-3 months remaining) plus I have ordered another ONT from here: Electroline FTTH ONU 1GE EPON EUZ01GS Optical Network Terminal - Buy Electroline FTTH ONU 1GE EPON EUZ01GS Optical Network Terminal Online at Low Price in India - Amazon.in

This "ElectroLine" ONT is unknown to me, does not seem to have presence in India so not sure about warranty claim plus the seller has only a single 5 star rating at the moment.

One thing I saw on my router logs is messages like "TCP FIN attack attempt" and "DDoS flood attack packets sent for 20 seconds from 192.168.1.1" the IP being the ONT so I don't know if my ONT is hacked with malware or this activity is just coming from the internet. The ONT itself does not have logs to view so can't be sure.

Never thought an ONT would fail so quickly. 🙁

So it seems my Digisol ONT is rebooting regularly only when my router is connected to it! If I directly connect my PC then it is stable for long duration 😀 Tried changing ethernet cables, factory reset and reconfigure of both ONT and router, tried a different router too, no luck.

Click to expand...

This feels a bit strange to me, could it be the power adapter of the ONT? That the ONT is unable to draw enough current and then it power cycles? Trying a different power adapter could be worth a try. (Although I am unsure as to why it would draw more current if its a router and less if its a PC 🤷‍♂️ 😆 )

Also, you are probably aware, your current ONT would most likely be whitelisted on the OLT side, so just swapping the ONT might not work, depending on how the OLT is configured.

Yeah I am hoping no whitelisting required for the other ONT but I will check with my LCO if any issues with the new one.

So my LCO guy came home today and replaced my Digisol ONT with an OptiLink one (it looks old not new) using the same power adapter and the SAME FREAKING ISSUE persists! It is stable when connected directly to PC but reboots repeatedly when connected to my wifi router!

Only thing is the other OptiLink is also (old not new) and same ZTE based chipset and has same web based UI as my DigiSol device so I am wondering if this OptiLink is also just defective. I remember many years ago when using 4g USB dongles, the ZTE one I had went bad pretty soon while the Huawei one worked fine for long time.

I have asked the LCO guy to get another power adapter for me, plus I am still waiting for that other ElectroLine ONU to be delivered from Amazon.

Totally weird and annoying situation 😀

varkey said:

Also, you are probably aware, your current ONT would most likely be whitelisted on the OLT side, so just swapping the ONT might not work, depending on how the OLT is configured.

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Looks like there is no OLT side whitelisting in my area as today the other ONT just worked after LCO guy connecting and configuring it at my side. I dont know if he maybe had it pre-whitelisted or something though. I will know when I get my new ONU I ordered online.

Yep, totally weird. Although I think it's the power adapter 😛, do you have another one lying around that you can just swap it with. As long as the voltage is around the same it shouldn't be an issue.

vishalrao said:

Looks like there is no OLT side whitelisting in my area as today the other ONT just worked after LCO guy connecting and configuring it at my side. I dont know if he maybe had it pre-whitelisted or something though. I will know when I get my new ONU I ordered online.

Click to expand...

Yeah, he probably just pulled another working ONT right seeing that it is not a brand new unit. Plus it doesn't seem to be user specific, so if an ONT is whitelisted it should work from any location coming under the same LCO/OLT.

varkey said:

Yep, totally weird. Although I think it's the power adapter 😛, do you have another one lying around that you can just swap it with. As long as the voltage is around the same it shouldn't be an issue.

Click to expand...

I tried with another adapter from an old Belkin router I had, device seems to power up and work but the same problem persists. 🙁

Now last thing to try before I pull out my non-existent hair is the new ONT due to arrive from Amazon, plus also asked my LCO to get a new ONT for since mine is still under warranty but that will take a few days I guess - will report back later.

Update! Breaking News! (TLDR) Looks like using the ONU in bridge mode works around the rebooting problem and my connection is now stable! 😀

Today I tried fiddling around with some more settings and managed to figure out how to set my OptiLink ONU to bridge mode (I guess) and put the BSNL FTTH username/password on my Netgear router.

At first it didn't work but then I put the VLAN ID and selected all LAN ports and WiFi radios in an obscure section of the Netgear advanced config called "VLAN/IPTV settings" 😀 And lo and behold it worked!

It authenticated and connected fine without needing to get any OLT whitelisting done (no need to clone any MAC) so not sure if the LCO guy has configured the PON MAC (instead of the WAN MAC) or none at all.

Connection has been up and stable for more than an hour now whereas before it would reboot within 20-30 minutes or less, so fingers crossed it stays this way.

So it must be the NAT module of the ONU's operating system (ZTE chipset) which is unstable and probably crashes (causing the ONU to reboot) with multiple client devices connecting and sending traffic to it. When I had earlier tried only connecting my PC via LAN to router and disabled wifi so that only 1 device was connected the ONU again seemed to be stable thus leading me to believe the NAT module is the culprit.

@varkey Earlier I thought my ONU did not support bridge mode because there was no explicit mention of it in the UI but all I needed to do was delete the WAN configuration where the BSNL username/password was provided and leave it blank/empty. That apparently leaves the ONU in bridge mode by default even though DHCP server feature is enabled. I just gave it a shot in the dark and this worked! 😀