Fibre into DrayTek

Hi

Our main router is DrayTek 2866 which connects to our LAN with its own broadband (WAN 1). A second fibre connection Cisco 1117 router feeds into DrayTek 2866’s WAN 2.

I setup WAN 2 on Draytek with the fixed ips provided by fibre provider using DrayTek’s ‘Static or Dynamic IP’ option instead of ‘PPPoE’. This setup worked for a few weeks. The only problem was the speed seemed low for a 100Mbs connection.

1. Yesterday our internet connection went down and the only way we could get internet connection was to disconnect fibre cisco router from the Draytek 2866. It seems when Cisco is connected to WAN2 of Draytek 2866, it also takes down Draytek 2866’s own broadband connection (WAN 1). Do we know why this is happening? As the usual expectation would be that if Cisco develops fault Draytek will continue to provide internet through its main broadband connection.

2. Is there anything wrong with my setup that needs fixing?

3. There are four ports on fibre Cisco 1117 but seems only one port is hot. Is there a standard method to find out the correct port to connect to?

Thanks

Regards

In reply to a post by Johm007:

It seems when Cisco is connected to WAN2 of Draytek 2866, it also takes down Draytek 2866’s own broadband connection (WAN 1). Do we know why this is happening? As the usual expectation would be that if Cisco develops fault Draytek will continue to provide internet through its main broadband connection.

To your latter point - only if the Draytek understands that there is a problem with the Cisco WAN connection.

For example in a proper network/optical interface failure between you and the POP/exchange on the leased circuit, then the ADVA will drop its LAN connection though link loss forwarding to the Cisco. The Cisco will then do likewise and drop it onward connection to the Draytek. To the Draytek WAN2 appears physically dead or disconnected and (hopefully if its been setup correctly) fails-over to LAN1, its xDSL connection.

However there could be issues related to routing or packet forwarding - your internet connection still does not 'work' but neither does your Draytek necessarily understand that as it still see a live connection on WAN2. Its till thinks its OK, even if it not in reality. Other tests would need to be done by the Draytek (like routing or reachability tests) to determine if WAN2 was good or not.

So there's different types of levels of WAN "faults" and it may be that the Drayetk 'failover' can only detect the most basic level of outage - a full disconnection.

Edited by Pheasant (Fri 12-Nov-21 00:16:06)

On my 2925 on the ‘Static or Dynamic IP’ page there is section 'WAN connection detection' with various options. I have played around with these and you can get the Draytek to report a WAN connection when there is none or not detect one when there is one.

I use ping detect but there is also 'Always on' eg no check, ARP and Strict ARP.

I used these options to troubleshoot a Mikrotik router in bridge mode, found that another item on the LAN was grabbing the Bridge connection before the Draytek, which was solved by telling the Mikrotik to only accept connections from the Draytek's MAC address.

Edited by kommando (Fri 12-Nov-21 08:52:33)

Have you set up load balancing between the two WAN connections? Or Load Balance/Route Policy stopping network clients from using the Failover WAN? You probably already know this, but for Failover to work, you need to tell it to Failover when one of the links goes down, if you don't then you will lose connectivity if the "default WAN" goes down.

I run two WAN connections into a 2926 and everything works perfectly (my recent post on my BQM notwithstanding). If you aren't sure, take a look at WAN / General Setup and let us know what you see at the top under "Load Balance Mode" and under WAN1 and WAN2 "Active Mode".

I have a Draytek 2860 using two connections, VirginMedia and BT. I have it setup for loadbalabcing and it just works. The last time VM dropped the line I didn't even notice.
They are set to Always On, Load Balanced. The VM line is ARP detect and the BT line is PPP detect.

Hi

Failover is in place I suspect the Draytek could not detect the Cisco side fault and kept routing traffic to it.

Regards

In reply to a post by Johm007:

Hi

Failover is in place I suspect the Draytek could not detect the Cisco side fault and kept routing traffic to it.

Regards

You need to change the WAN detect mode
https://www.draytek.com/support/knowledge-base/4809

OP would need to select “Ping detect” otherwise it won’t drop the dodgy connection (unless a JCB has gone through the fibre or the ilk)

I've not seen an ISP that configures their managed routers to forward a link loss, usually part of the troubleshooting involves determining that the LAN side is up.

Fair enough. I’m going off my unmanaged connection which definitely forwards the link loss.