Router "B· = rb600 in bridge mode. Ether 2 connects to Router "C" and is in bridge, Ether1 connects to Router "A" and is also in bridge.
Router "A" = rb1000 as main gateway. Ether1 connects to Router "B", Ether2 connects to other router for route to other ISP "Y", Ether3 connects to my LAN network.
ISP delivers 20Mb symmetrical fm Router "C" to my network.
Router "B" has firewall on bridge enabled and is having mangle filter for Queue Tree use and thus QoS.
Router "A" is having 250+ simple queues for clients and performs firewal filter and also policy routing for clients traffic to decide to go to gw of provider "X" or via other interface to provider "Y".
Since a year I have regurlar random ethernet interface of rb1000 failure on the LAN facing interface. After long investigation found that before this happens memory usage was building up. Probably causing the ethernet interface failure. To troubleshoot/find reason why/find solution one of the things we did was to disable the Auto Negotiation (speed) of ethernet interface of rb1000 on both LAN and WAN end. (This last one connects to Router "B"). It looked it didn't have any effect on the traffic so no harm done (I was presuming.......)
Before, with auto negotiation on "A" interface Ether1 (to rb600>to WAN) the link settled at 1Gbps full duplex.
after disabling auto negotiation we set link fixed to 100Mb.
Since then many complaints fm users building up; "internet was slow". But on tests I performed could not find anything. Al local network ran fine and each client also noted that speedtests showed their normal speeds but all kind of streaming contect didn't work or very poor!
My monitor PC now also developped a slow connection to the internet. (While it is bypassing all filters/queus for testing ISP speed.) Only after opening 8 or more separate download programma's with each many connections I was able to reach a near 20Mb download. Upload was always around 10Mb. (Included client traffic running over it at the same time.)
Before I only had to open one download program to get my full 20Mb down and 18Mb upload in one program/test session.
I spend 3 days checking all my filters, queues, settings etc. and ended up even disabling them all to make my PC sole user. Nothing more then 4-5Mb to squeeze on a single program (but multiple connections) download.
Then, while my brain was filled with endorfine after a toilet visit it struck me!
Did I not change that interface speed setting???So, inmediately set the interface back to "auto negotiate" and the link settled again to 1Gb full duplex.
Did a test and YES, one single program could download again at the full available speed of the ISP!
For good sake I disabled "auto negotiation" again and yes, speed was gone again. Back to 4-5Mb download (but still 10Mb upload!)!
For more good sake set now the speed to 1Gb but left "auto negotiate" disabled. Link status showed "link ok" again and rate showed 1Gbps but no traffic at all was possible!
Set interface back to "auto negotiate" again and after some time (routing table cache refreshment) traffic started to flow again and a single download test gave me 20Mb down and 18-19Mb upload again!
Can someone explain why a link that is showing 100Mbps as connection rate gives this kind of problem and only allows about 4-5Mb traffic in one direction?
I first want to know if anybody has similar issue or noticed similar before I am going to write to MT support about it.
Main important thing is that the issue can be reproduced so possibly this is an investigable bug.