21CN pain

My line was swapped over to the 21CN about a month ago. A day or so later, I 'upgraded' my service, to ADSL2+ or whatever it's called these days , mainly to be able to take advantage of faster upload speeds - as a photographer, uploading pics is common for me.

However, I am beginning to wish I hadn't bothered now, as I've had little else but pain since doing so.

Previously, I was synching at 4400 upwards and my line was quite stable.

After upgrading, I had trouble with my router - a Linksys WAG54GX2. It would sync fine, but wouldn't connect to Zen. I flashed it with the latest firmware which then gave me the option for ADSL2+ and then it would connect fine.

But, for some bizarre reason, after almost random time intervals - typically anything from 20 mins to several hours, I could not access sites by name, though pinging them numerically would work, hence I suspected a DNS issue. Rebooting the router would cure this, until it would lose them again and keep doing this cycle. Also I noticed that none of the computers on my network were shown in the router control panel as being connected when this happened.

So, speaking to Zen support, I ended up buying a new router and ended up with a Netgear DGN2000 as a distress purchase at my local branch of Currys - normally I'd have looked online.

This would connect fine and initially seemed ok, but had a lower sync speed - on ADSL2+ the Linksys would still connect around 4000, but the Netgear tended to be around 3000 and lower.

Sadly though, I'm still seeing the same symptoms as with the Linksys - losing DNS and my connection is no where near stable and my router is being rebooted several times per day - many times do I come back to my computer to find that I can't reach anywhere and the only cure is yet another reboot.

This must also have had a negative effect on my line speed, as it will now no longer sync above about 2200.

I'm tearing my hair out now, so any help is welcome!

Switch off DNS relay on the router and set the DNS servers on your PC's that should stop the crash.

Pick some nice open DNS servers if you don't want to use Zen's - google and opendns both offer lookup servers you can use.

As for the sync speed - I don't know who's chipsets those routers use, but if you could post your line stats from the router your using at the moment we might be able to comment.

As for not getting above 2200 it sounds like DLM don't like you very much (like it don't like me) once you have posted your line stats we can better advise.

As a matter of interest, I've flashed the routers firmware to use the DGTeam firmware and I'm impressed with it - it enables all manner of other settings and tweaks if so desired and has better stats reporting for use in diagnosing problems.

Here's the extended stats:-

/usr/sbin/adslctl: ADSL driver and PHY status
Status: ShowtimeRetrain Reason: 8000
Channel: FAST, Upstream rate = 664 Kbps, Downstream rate = 2272 Kbps
Link Power State: L0
Mode: ADSL2
Channel: Fast
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 9.6 8.9
Attn(dB): 51.0 29.6
Pwr(dBm): 0.0 12.9
Max(Kbps): 4612 664
Rate (Kbps): 2272 664
G.dmt framing
K: 36(0) 21
R: 16 12
S: 1 4
D: 64 8
ADSL2 framing
MSGc: 59 12
B: 35 20
M: 1 4
T: 2 4
R: 16 12
S: 0.5000 4.0000
L: 832 192
D: 64 8
Counters
SF: 75857 68400
SFErr(CRCErr): 0 0
RS: 9861430 1231215
RSCorr: 1198 135
RSUnCorr: 0 0

HEC: 0 0
OCD: 0 0
LCD: 0 0
Total Cells: 6602667 547229
Data Cells: 1026 413
Drop Cells: 0
Bit Errors: 0 0

ES: 0 0
SES: 0 8
UAS: 49 0
AS(Uptime): 1233

INP: 4.92 2.00
PER: 16.25 18.00
delay: 8.00 8.00
OR: 32.00 8.00

Bitswap: 2 0
Total uptime: 1233

Total time = 21 min 44 sec
SF = 75857
CRC = 0
LOS = 0
LOF = 0
ES = 0
Latest 1 day time = 21 min 44 sec
SF = 75857
CRC = 0
LOS = 0
LOF = 0
ES = 0
Latest 15 minutes time = 6 min 44 sec
SF = 24936
CRC = 0
LOS = 0
LOF = 0
ES = 0
Previous 15 minutes time = 15 min 0 sec
SF = 50921
CRC = 0
LOS = 0
LOF = 0
ES = 0
Previous 1 day time = 0 sec
SF = 0
CRC = 0
LOS = 0
LOF = 0
ES = 0
Showtime Drop Reason: 8000
Last Retrain Reason: 8000


I'm almost encouraged by the Max Kbps rate of 4612 - now I'm still synched at 2272, but does that look like what's possible with those stats?

I've been talking to Zen about this - notably Brad in technical support and I'm awaiting a call back to see what the results are from tests that were going to be carried out this last weekend on this issue. It seems that I'm not the only one to be seeing similar things and Zen (Leo) thinks it may be a line card issue at the exchange / compatibility issue - that's another reason why I'm trying the DGTeam firmware to see if that improves things.