Richard J. Sears said:
We have changed multilink bundles, tried different types of switching and route caching, turning on and off fragmentation - the only thing
[snip]
dCEF is enable on both routers, however the problem remains the same even after disable dCEF.
Your last line, I think, is rather interesting. I have a 7513 with essentially the same hardware as you (ct3, fe's, etc) and was recently doing testing with red/wred. I had read the notes about dCEF and how this changes/limits some of what one can do with red/wred; as with dCEF enabled, the queueing happens on the VIP instead of the RSP. During testing, I setup a wred config on several interfaces and everything worked fine -- while using standard CEF. Later on, I enabled dCEF and began to test (d)wred. I found the limitations on parameters were a killjoy, so I tried backing out of dCEF/dwred. Interestingly, I couldn't back out. Even if I negated all the wred commands and disabled dCEF, the 'sh int' would still report the VIP was doing all the work. After more attempts and various ideas, I just reloaded the damn thing -- it came back up with, as I had hoped, the VIP no long doing wred, but rather the RSP. So, I wonder whether or not the mlppp instability isn't due to some obscure or yet undiscovered dCEF bug and also if when you disable dCEF, it's not really getting disabled. Maybe disable dCEF -- then reload? It may also help to get more familiar with the forwarding path data takes in this scenario; I'm not familiar with cisco's mlppp enough to know if all the encapsulation and multi-link work happens rsp side or vip side.
Cisco Internetwork Operating System Software IOS (tm) VIP Software (SVIP-DW-M), Version 12.2(13)T5, RELEASE SOFTWARE
Also, instead of following 12.2, maybe try the 12.0(S) train, if you're not needing specific features in 12.2. I've surveyed several other folks recently about which version they run; 12.0 S-line seems to be the least-hated and more-stable train. It sounds like (at this point) it'd be worth trying just about anything to get the mlppp links stable. <G> --Tk