On Thu, 21 Mar 1996, Mark Boolootian wrote:
I'm interested in knowing what happened between March 6 and March 7 on the Ames FDDI ring. That's when the utilization jumped from around 60% to 90%. Also of interest is that it appears MFS stopped collecting stats late in the afternoon, with utilization around 60%, on the 6th, and didn't start collecting again until around noon on the 7th, at which time utilization is running at 90%.
Anyone know what happened?
Something along the lines that we noticed the NetEdge's were no longer collecting proper statistics on the FDDI interfaces. Rather than measuring total traffic, it only measured traffic that was forwarded over another link. We switched the data collection around which caused the hiccup in the graphical statistics. On March 20th, Lance Tatman, notified the MAE-West customers via the mailing list, that NASA had procured funds to obtain a Gigaswitch and that he is expecting delivery "towards the end of March." Once that Gigaswitch is received, we will solve two problems. #1) Congestion on the FDDI at Ames. #2) Is caused by #1, in that the NetEdge is having to "think" about discarding packets it cannot deliver onto the existing FDDI due to congestion. Secondly, we could *possibly* be running into a CPU limit on the NetEdge's where it's coming closs to it's PPS processing limit. #2 will be rectified by removing the NetEdge's from service, and terminating the OC-3c on the DEC Gigaswitch itself. However, in order for this to happen, NASA has to turn up its Gigaswitch. ;-) Between now and the time the Gigaswitch is turned up, several Ames connected carriers are obtaining connections into the San Jose (MFS) Gigaswitch. This should provide them additional redundancy and reduce load on their backhaul links as well as the individual "sections" of the MAE. -jh-