On 11/23/05, Stephen Hemminger <shemminger@xxxxxxxx> wrote: > On Wed, 23 Nov 2005 09:10:56 -0800 > Bob Snyder <oceansidebob@xxxxxxxxx> wrote: > > > Hello, > > > > I have built a data link system (i.e. microwave radio) with bridges at > > both ends of the link (sort of back-to-back). The data link boxes have > > highly asymetrical RS-422 serial interfaces which are interfaced to > > the bridges with dscc4/hdlc/syncppp modules. Also, the bridges each > > have one regular ethernet port. The intention is to have the ethernet > > at one end appear to be connected to the ethernet at the other end. > > Also, one end is usually connected to a busy lan with lots of > > broadcast traffic. The bridges are running on 266 MHz Pentiums with no > > other load. > > > > The system works in general, but sometimes there are very long and > > erratic delay times (up to several seconds) when pinging through the > > link. If the radio link is brought up before the bridges are started, > > things seem to work well (ping times of ~10-15 ms). The problem seems > > to occur if the bridges are started before the radio link is brought > > up. Once the problem appears it will persist until the bridge is > > restarted. > > > > I wondered if the problems is that the MAC table was getting too big. > > I reduced the ageing time from 300 to 30 seconds, and this seemed to > > help (the MAC table got smaller), but the problem persists. Also the > > problem can be seen sometimes when not connected to the lan, so maybe > > I just don't have the bridge configured properly. > > > > Any help or suggestions appreciated. > > > > Does the interface implement broadcast/muliticast? > > Also the bridge takes 30 seconds to go through the learning phase > when interface is attached per STP spec. > > -- > Stephen Hemminger <shemminger@xxxxxxxx> > OSDL http://developer.osdl.org/~shemminger > Well, I think so, since ARPs work, and I see lots of the lan's MACs on the side that isn't connected to the lan. (Don't know about multicast). The learning phase is observed (seems shorter than 30 seconds) but I don't know how that would relate to the problem. Bob Snyder
