Frustrating Problem - ADSL, Draytek Modem, Cisco RV082 Router

Forums › 2degrees (including Slingshot, Orcon, Flip, Stuff Fibre, MyRepublic, 2talk and Vocus) › Frustrating Problem - ADSL, Draytek Modem, Cisco RV082 Router

aaristotle

161 posts

Master Geek
+1 received by user: 37

#103510 8-Jun-2012 15:29

We have frustrating issue where we are unable to isolate the problem.
We use a Cisco RV082 dual WAN router to provide load balanced Internet redundancy via an Orcon HSNS circuit and ADSL connection (Purple+). This has been working for a number of years without any issues, and continues to work without the ADSL modem connected.
Last Thursday night (a week ago) the ADSL connection began running slowly and would only connect to google related sites. Clicking on search results would result in a blank page.
Initially plugging a laptop directly into the Draytek ADSL modem (in PPPoE / PPPoA translate mode) and connecting via PPPoE on the laptop appeared to work so we ordered a replacement RV082. Over the following days we found the Laptop PPPoE connection was not consistent so suspected the Draytek modem, and replaced that as well. With both new devices we still experience issues with slow/inaccessible websites, however when we connect an ADSL modem in default modem/router mode (ie it logs in using PPPoA) the ADSL connection seems to be working normally, although we haven't left it in this mode long enough to discover if the ADSL connection is intermittent. We have checked settings multiple times, and tried all sorts of combinations with inconsistent results for the same combination when repeated.
Does anyone have any ideas of what we might be missing, or any diagnostic methods we can try?

sorceror

163 posts

Master Geek
+1 received by user: 47

#638037 8-Jun-2012 22:06

sounds like you are running into MTU issues - try lowering the MTU to something like 1400 (try it on a PC first)

mercutio

1392 posts

Uber Geek
+1 received by user: 134

#638054 8-Jun-2012 22:32

orcon recently increased their MTUs from 1492 to 1500. You may have had clamping working before and not now. When using PPPoE you'll probably have to decrease your mtu. If you can do something called MSS clamping it could help.

Some more information about MTU: http://www.phildev.net/mss/blackhole_description.shtml

aaristotle

161 posts

Master Geek
+1 received by user: 37

#638829 11-Jun-2012 11:32

Thanks for the MTU pointers. I searched more specifically on RV082 and MTU and came across a number of threads dating back to 2006 with very similar problems relating to the RV082.
I'm guessing the RV082 hasn't handled the increase of MTU by Orcon and still has issues in the firmware around this. (Even though the new one is third generation HW, and the older is second generation).
We have also borrowed a Dlink Router and put this in front of the Draytek using PPPoE, and it all appears to be working fine.
It looks like we will have to replace the RV082 with something else.
Has anyone had experience of the VigorPro 5300 with Orcon ADSL in a Load balanced mode?
Any other recommendations for a Dual WAN Router for use with ADSL and HSNS connections?