Connection:

Fibre-Optic Leased Line, 100Mbit over 1Gbit bearer.

Hardware:

ADVA FSP 150-GE102Pro
Cisco C1117-4P
DrayTek 2862Lac (Firmware Version 3.9.8.1_BT)

The ADVA and Cisco are connected together using a fibre patch cable, while the DrayTek and Cisco are connected using a standard network cable. I have tried using both CAT5 and CAT6 cables between the DrayTek and Cisco but to no avail.

On the DrayTek dashboard, the WAN2 port is green and I have that port set to Auto Negotiation. I can also ping the Cisco's IP address.

However, when I set it to "1000M Full Duplex" and reboot the DrayTek, the WAN2 port on the dashboard is still green and there are 2 green LEDs on the WAN2 port and 1 green LED on the Cisco, but no throughput. I can't even ping the Cisco's IP address. The DrayTek reports WAN2 as being "DOWN" and the SysLog Viewer does not report any errors or connection attempts.

I have tried setting the WAN2 port to "100M Full Duplex", which the dashboard shows WAN2 as orange, but there is throughput and I can ping the Cisco's IP address.

The reason I am doing all of this is because all our downloads are coming through at 2MB/s. There is QoS applied but the downloads fall under "OTHER" which is currently 70% of the 100Mbit connection. But even with QoS disabled, there's no change to the download speed and setting the WAN2 port to "1000M Full Duplex" still results in no throughput.

Can anyone help explain why there's no throughput when manually setting the WAN2 port speed/duplex?

Could the Cisco be incompatible with the DrayTek? I already spoke to the ISP who suggested replacing the Cisco if an incompatibility was proven.

I wanted to post an update in case anyone else experiences a similar issue.

This was reported to DrayTek Support and after an hour-long telephone conversation, the technician concluded the Cisco was at fault, not the DrayTek.

If I connect a laptop or even a switch to WAN2 and set the port to 1Gbit, it works. Likewise, connecting the crap Vigor 2927 I posted about last night to the Cisco and setting the WAN port to 1000M Full Duplex... Works fine!! I even noticed the throughput is quicker than when the port it set to Auto Negotiation.

So, if anyone else is experiencing this issue, your only solution is to buy a brand new router!

We had a very very similar issue with the 2832n when it was first released and after a couple of months of emails with support a new firmware appeared that resolved the issue.

That's what I had hoped would happen, but telephone support said it was unlikely because the Vigor 2862 is an old router apparently.