Line Sync Problems...

[SYNERGY]

Hey there

Can anyone shed some light on what could be the possible problem?

Stats and log below- Thanks.

Couldn't increase MTU to 1500
Nov 28 09:12:12 PPPoE: bil_ipcpup:end
Nov 28 09:12:45 syslog: NTP current time is Sun Nov 28 09:12:45 2010 
Nov 28 09:13:23 DHCP SERVER: DHCP request from d8:a2:5e:6e:ea:9d
Nov 28 09:13:23 DHCP SERVER: DHCP ack to d8:a2:5e:6e:ea:9d
Nov 28 09:22:25 syslog: Linesync lost
Nov 28 09:22:45 syslog: Linesync achieved
Nov 28 09:22:45 syslog: Downstream rate: 3328 kbps
Nov 28 09:22:45 syslog: Upstream rate: 512 kbps
Nov 28 09:23:05 syslog: Linesync lost
Nov 28 09:23:20 syslog: Linesync achieved
Nov 28 09:23:20 syslog: Downstream rate: 4096 kbps
Nov 28 09:23:20 syslog: Upstream rate: 480 kbps
Nov 28 09:23:26 syslog: Linesync lost
Nov 28 09:23:46 syslog: Linesync achieved
Nov 28 09:23:46 syslog: Downstream rate: 4096 kbps
Nov 28 09:23:46 syslog: Upstream rate: 512 kbps
Nov 28 09:27:28 DHCP SERVER: DHCP request from d8:a2:5e:6e:ea:9d
Nov 28 09:27:28 DHCP SERVER: DHCP ack to d8:a2:5e:6e:ea:9d
Nov 28 09:36:42 syslog: Linesync lost
Nov 28 09:37:02 syslog: Linesync achieved
Nov 28 09:37:02 syslog: Downstream rate: 4096 kbps
Nov 28 09:37:02 syslog: Upstream rate: 512 kbps
Nov 28 09:42:26 DHCP SERVER: DHCP request from d8:a2:5e:6e:ea:9d
Nov 28 09:42:26 DHCP SERVER: DHCP ack to d8:a2:5e:6e:ea:9d
Nov 28 09:43:39 syslog: Linesync lost
Nov 28 09:43:59 syslog: Linesync achieved
Nov 28 09:43:59 syslog: Downstream rate: 4096 kbps
Nov 28 09:43:59 syslog: Upstream rate: 512 kbps
Nov 28 09:44:05 syslog: Linesync lost
Nov 28 09:44:22 syslog: Linesync achieved
Nov 28 09:44:22 syslog: Downstream rate: 4096 kbps
Nov 28 09:44:22 syslog: Upstream rate: 512 kbps
Nov 28 09:44:41 syslog: Linesync lost
Nov 28 09:44:55 syslog: ^M
Nov 28 09:44:55 syslog: ^M
Nov 28 09:44:55 syslog: --->RPKT_LOST   ^M
Nov 28 09:44:56 syslog: ^M
Nov 28 09:44:56 syslog: --->RPKT_LOST   ^M
Nov 28 09:44:56 syslog: ^M
Nov 28 09:44:56 syslog: Linesync achieved
Nov 28 09:44:56 syslog: Downstream rate: 4096 kbps
Nov 28 09:44:56 syslog: Upstream rate: 512 kbps
Nov 28 09:47:02 syslog: Linesync lost
Nov 28 09:47:33 syslog: Linesync achieved
Nov 28 09:47:33 syslog: Downstream rate: 4096 kbps
Nov 28 09:47:33 syslog: Upstream rate: 512 kbps
Nov 28 09:57:23 DHCP SERVER: DHCP request from d8:a2:5e:6e:ea:9d
Nov 28 09:57:23 DHCP SERVER: DHCP ack to d8:a2:5e:6e:ea:9d
Nov 28 09:57:24 syslog: Linesync lost
Nov 28 09:57:51 syslog: Linesync achieved
Nov 28 09:57:51 syslog: Downstream rate: 4096 kbps
Nov 28 09:57:51 syslog: Upstream rate: 512 kbps

Line info:
ADSL Mode
Modulator
DSP FirmwareVersion DMT FwVer: 3.5.18.0_A_TC, HwVer:T14F7_1.0
DMT Status Up
Operational Mode ADSL G.Dmt
Upstream 512 kbps
Downstream 4096 kbps
Noise Margin (Upstream) 13.0 db
Noise Margin (Downstream) 16.5 db
Attenuation (Upstream) 12.0 db
Attenuation (Downstream) 27.0 db


Tried a Billion 7300 & Dlink. Same problem.
Port Filters on all phones.

Thanks

 

[Gordon_R]

I'm not sure which settings you need to adjust, but the message "Couldn't increase MTU to 1500" sounds very dodgy...

I've always been told to use MTU of 1492 for PPPoE.

 

[SYNERGY]

I'm not sure which settings you need to adjust, but the message "Couldn't increase MTU to 1500" sounds very dodgy...

I've always been told to use MTU of 1492 for PPPoE.

Yeah I know- but tried 2 different routers.

Edit: Router was set to 1472. Changed to 1492. AFAIK that affects packet size?

 

[Pada]

MTU affects the maximum packet size that can be transmitted. ADSL's MTU cannot be higher than 1492.
If you decrease the MTU, then you can reduce your latency, but you will also reduce your maximum throughput considerably.

Has this started only recently?

If your ADSL modem isn't connected via a filter, then it could disconnect like that.

 

[ichigo]

does the weather affect the line and is their a pattern when the line drops like time etc. or is it random

 

[SYNERGY]

@ Pada: Not connected to filter. Thanks for the latency info might use it.

Weather doesn't affect it.

 

[Pada]

Synergy, you really have to connect the ADSL modem via a filter! You can get the ADSL splitter/filter for like R50 from a Telkom shop.
Please note that you cannot use the same filter that you're using for the Telephones for the ADSL modem, because they make use of different filters: low pass filters for the phones/fax machines/alarm systems and high pass filters for the ADSL modem.

I don't know if changing the MTU would actually give you any noticeable latency benefits in terms of gaming or so.
Personally, I would keep the MTU set at 1492, but you're welcome to play with it

 

[fxit_man]

Really? (About the filter part)

I was always told there must be no filter between the router and telephone line...

If so maybe I must go get one.. Sometimes get disconnects when receiving/sending a fax for some weird reason

 

[SYNERGY]

Synergy, you really have to connect the ADSL modem via a filter! You can get the ADSL splitter/filter for like R50 from a Telkom shop.
Please note that you cannot use the same filter that you're using for the Telephones for the ADSL modem, because they make use of different filters: low pass filters for the phones/fax machines/alarm systems and high pass filters for the ADSL modem.

I don't know if changing the MTU would actually give you any noticeable latency benefits in terms of gaming or so.
Personally, I would keep the MTU set at 1492, but you're welcome to play with it

Will try it. Telkom advised there must be no filter between the router and phone line, and never had one for the past couple years but will give it a try.

Thanks Pada.

 

[Pada]

Well, I could be wrong about the filter that is required for the ADSL to prevent disconnects, but it would definitely reduce the amount of noise on the telephone due to "leaks" from the ADSL modem.
I'm running my D-Link DSL-2500U via an ADSL splitter/filter that I bought from the Telkom shop, but I haven't opened it to check if it actually filters the ADSL port.

If you have an alarm system or fax machine, make sure that it is connected via a filter too!

It should be pretty simple to test whether you require a filter or not for the ADSL modem - simply make a phone call to your land line (I don't think you even need to pick up the call) and see if the modem resets/loses sync.

 

[ichigo]

Well, I could be wrong about the filter that is required for the ADSL to prevent disconnects, but it would definitely reduce the amount of noise on the telephone due to "leaks" from the ADSL modem.
I'm running my D-Link DSL-2500U via an ADSL splitter/filter that I bought from the Telkom shop, but I haven't opened it to check if it actually filters the ADSL port.

If you have an alarm system or fax machine, make sure that it is connected via a filter too!

It should be pretty simple to test whether you require a filter or not for the ADSL modem - simply make a phone call to your land line (I don't think you even need to pick up the call) and see if the modem resets/loses sync.

Adsl portion has no filter, the splitter only has the filter for the phone side