Adsl Led Turns Off At Random - Need Power Off/on To Establish Connection

[knura]

My problem is different from that described under another topic Modem Adsl Light Not At All Blinking

I have a D-Link 502T modem. This is my second modem from MTNL and in service for 14 months - the first one RIP'd in 2 months.

For the past couple of months, the ADSL LED goes OFF randomly - there is no pattern. Sometimes this does not happen for days and sometimes it happens 2-3 times in a day. All other LEDs are BLINKING. I can ping the modem on it's LAN port 192.168.1.1 and access it via HTTP and TELNET but no traffic to the 'Net.

Soft reboot (thru telnet session) does not fix the problem. To restore the ADSL connection I have to power cycle the modem.

The problem could either be in the DSLAM card @ the local exchange or in my modem. I have lodged a complaint with MTNL but no response so far. The problem is that once the modem is power cycled, the DSL connection comes back into service. The guys @ MTNL will claim nothing is wrong with the modem.

Anyone else experienced this? What did you do to solve the problem.

 

[ogtripleog]

i think that this is most probably a problem with ur line.. login to ur router and check the line stats such as snr ratio and attenuation.. some modems will lose sync if the snr is too low. also some D-Link modems have had problems with this and u might try updating the firmware

 

[cyberwiz]

is ur router connected to a UPS?

 

[knura]

Good points ... The firmware is latest (May/2005). When the modem is sync'd to the ADSL line the parameters are as follows:

Max Tx Power -38 dBm/Hz

Item Downstream Upstream Unit
SNR Margin 31 25 dB
Line Attenuation 18 9 dB
Data Rate 256 256 kbps

I am located ~2 Kms. from the local exchange. It would be interesting to see how other users
fare with the above params.

QUOTE(cyberwiz @ Nov 10 2006, 02:31 PM) [snapback]68364[/snapback]
is ur router connected to a UPS?
[/b]

Yes, I have a UPS supplying power to my router, 2 ethernet switches via a power strip. What is the significance of the UPS?

 

[ogtripleog]

sorry man all i can say is try some other modem on the same line and if it is resolved then it's the modem.. unless someone else can think of a better idea

 

[cyberwiz]

Ur line stats are normal,therefore i feel that my hunch is correct. I think ur problem is related to the power fluctuation. Actually there is a flaw in DSL 502T, ie. whenever there is a power failure/fluctuation the DSL 502T will lose the ADSL link inspite of being connected to the UPS and will never recover. During this time the other lights remain normal and the modem remains pingable and also responds on port 80 ie web interface...

 

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[ogtripleog]

yea but wasn't this fixable by firmware? are u sure u have the latest firmware?

 

[knura]

QUOTE(cyberwiz @ Nov 10 2006, 08:55 PM) [snapback]68397[/snapback]
Ur line stats are normal,therefore i feel that my hunch is correct. I think ur problem is related to the power fluctuation. ... snip ...
[/b]

Shouldn't more subscribers with the D-Link 502t be experiencing this sympton if the power fluctuation (given that is fairly common) is causing the modem to loose sync on the ADSL port?

By chance, I also came across the local phone linesman tinkering @ the neighborhood jn. box earlier today. When I described my problem he said the something similar about the modem's power brick; that the power brick was the culprit. Since my modem is rented, he said MTNL would replace it. Apparently, it is a known problem to MTNL yet my complaint @ the local exchange has not been looked at.

I'll take this modem to MTNL next week and hopefully, the replacement will work properly.

Thanks to all who participated

This is what I have - Firmware Version : V2.00B01T01.ML.20050530. Just checked DLink's site - this is the latest version.

 

[cyberwiz]

QUOTE(knura @ Nov 10 2006, 09:48 PM) [snapback]68401[/snapback]
Shouldn't more subscribers with the D-Link 502t be experiencing this sympton if the power fluctuation (given that is fairly common) is causing the modem to loose sync on the ADSL port?
[/b]

Its an established problem already..i dont know why more ppl are not reporting..maybe they are not observant enough and attribute the problem to other things rather than the real culprit.

By chance, I also came across the local phone linesman tinkering @ the neighborhood jn. box earlier today. When I described my problem he said the something similar about the modem's power brick; that the power brick was the culprit. Since my modem is rented, he said MTNL would replace it. Apparently, it is a known problem to MTNL yet my complaint @ the local exchange has not been looked at.
[/b]

I doubt if even MTNL understands the problem..let alone a linesman..even dlink had a hard time figuring it out when i reported it to them..they couldnt come up with any soln and i had to ultimately change the modem

 

[chicmagnet]

well yeah i have this problem too.. but hmm. its rare ..so i dont bother...