Hi, I have a Vigor 2766 that I purchased to replace the Technicolor modem/router supplied by my ISP (Zen in the UK, via Openreach FTTC cabinet 50m away) which was hopeless for streaming video calls during the lock-downs. The 2766 is much better in that respect, but has two really annoying other problems, possibly related.

1. It seems slower than the Technicolor at establishing the VDSL connection (several minutes typically). This wouldn't be so bad except that it drops the connection several times a day and sometimes won't reconnect at all without a reboot. When it _is_ connected the line stats are all exemplary (see below).

2. It sometimes (a few times a week) gets into a state where I can ping through it (eg ping 8.8.8.8 works) but I can't get http:// or ssh:// or any other TCP/IP connections to work through it. Again a reboot (and painfully slow re-connection) seems to be the only remedy.

Any ideas? I am going to try a new microfilter as that's one thing I haven't tried, and I'll report back.

Chris
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Code:

Model Name Vigor2766ac System Uptime 00:43:05 Router Name DrayTek Current Time Thu May 18 2023 08:24:42 Firmware Version 4.4.2.1_BT Build Date/Time Jan 10 2023 14:04:09 DSL Version 12-3-2-3-0-5 LAN MAC Address xx-xx-xx-xx-xx-xx Line Statistics Downstream Upstream Actual Rate 79299 Kbps 20000 Kbps Attainable Rate 117642 Kbps 22759 Kbps Path Mode Fast Fast Interleave Depth 8 1 Actual PSD 13. 5 dB -4.-2 dB Near End Far End Trellis ON ON Bitswap OFF OFF ReTx 1 1 SNR Margin 18 dB 9 dB Attenuation 11 dB 0 dB CRC 85 1 FECS 118225 s 0 s ES 4 s 0 s SES 0 s 0 s LOSS 0 s 0 s UAS 0 s 0 s HEC Errors 0 0 RS Corrections 0 0 LOS Failure 0 0 LOF Failure 0 0 LPR Failure 0 0 NCD Failure 0 0 LCD Failure 0 0 NFEC 240 244 RFEC 0 8 LYSMB 5028 20632

PS Problem #2 doesn't seem to be related to DNS resolution, as I can't ssh to a numeric IP address when it's in this state. Chris.

Don't know the answer to 2., but 1. is related to possibly Vectoring being enabled on your line (as suggested by your speed rate), and possibly the Technicolor modem not being Vectoring enabled. Typically vectored lines take around 5 min to establish a connection, regardless of the router (as long as it has Vectoring support).

Effectively, your line is up to 50Mbps, but with Vectoring technology, it runs faster: https://www.draytek.co.uk/support/guides/kb-what-is-vdsl-vectoring-sra-and-ginp

Since you have interleaving on your line, this looks like a line fault, resulting in a dropped connection several times a day, especially given the length to the cabinet (50m only!), you should have fewer if any dropped connections. You should get your line tested by ZEN as a precaution. Over 3 disconnections per day is considered a line fault, though I'm unsure if this is my provider's Openreach's interpretation.

You can also use non-vectored firmware on Drayteks, but I can't fully remember if this speeds up establishing a connection (most like, though). Please search for one of my posts where different modem codes are explained in terms of whether they support Vectoring or not.

Finally, you may want to experiment with different modem codes to see if they offer more stability. The BT firmware is only 'BT' because it's been tested on UK lines. You can use other modem codes, especially that each line is different (again, search for my posts about different modem codes).

I just noticed that you posted full stats 🤭

So, it looks like you have a line fault. Your SNR margin should be 6dB and it's 18dB for downstream and 9dB for upstream. But this could also be due to disconnections, though perso ally, I'm more inclined to think the former.

Thanks so much for your help. Will contact Zen and see what they say. I will also try a new filter, but it won't be completely straightford because of the relative positions of the router and master socket.

Cheers

Chris

Keep us posted.

Yes, the problem could be due to a faulty filter, too. Openreach's system that Zen uses will tell them if there's an issue and if so, where (customer premises).

If you want to test the filter yourself:
If you take the filtered faceplate off, you'll see the test socket. You can plug a dangly (it's sometimes referred to as rat's tail) filter into the test socket.