To answer your last question, since the packets that are punted to software for switching are handled by one of the EARL7 rate-limiters, which don't have counters and also you cannot see what packets, are being punted to software, the best option would be use
CPU-SPAN, to SPAN the traffic destined to RP-CPU and analyse that. sukumar Oh well. I found the problem - someone leaked too many prefixes, and it's %MLSCEF-SP-7-FIB_EXCEPTION: FIB TCAM exception for IPv4 unicast, Some routes will be software switched. Dunno why it's showing *these* symptoms, affecting some interfaces more than others. But still I'm interested in finding out how to see what packets are not being MLS/CEF-switched, and why, for the next round of debugging :-) -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Gert Doering Sent: Friday, January 25, 2008 8:07 AM To: [email protected] Subject: [c-nsp] 7604/Sup720 not MLS/CEF switching Hi, I could use a hint to start nailing this down. We have two 7604/Sup720s with 12.2(18)SXF7 here, doing a pretty similar traffic load (about 2-3 Gbit/s aggregate), and similar traffic pattern. IPv4, IPv6, MPLS, netflow export for IPv4. One of the boxes is running at 1-2% CPU, the other one is running at 60-80% (which started at 22:18 yesterday evening, with no significant change in traffic patterns). So, it's moving packets with a CPU not meant to be used for this. So I've checked two interfaces with very similar usage patterns (audio streaming of life radio, long-lasting flows with medium-to-large packets sizes), and there's a big difference in the percentage here: vlan1700, about 4% "not MLS/CEF switched": Protocol Path Pkts In Chars In Pkts Out Chars Out IP Process 25150 24734247 0 0 Cache misses 0 Fast 1328140746 1350996135423 191 58674 Auton/SSE 30723864532 30882213532050 18184117236 1335974238797 vlan4062, about 0.1% "not MLS/CEF switched": Protocol Path Pkts In Chars In Pkts Out Chars Out IP Process 368914 54599634 31636639 3543640264 Cache misses 0 Fast 1670054191 1924596882515 168 9913 Auton/SSE 1029709651247 1137649776167566 229040036204 16614962888496 there's difference on L2 for these interfaces (4062 is coming in via a dedicated port, 1700 is coming in via a trunk port), but I don't think this should make any difference. Most of the egress traffic for this is going via a L3 port-channel, or via a single L3 port. For both VLANs. Traffic level is about 400 Mbit on vlan 1700, 500 Mbit on vlan 4062, most of it "incoming". No big difference here either. Similar PPS levels, about 50.000 pps incoming. This is how vlan1700 looks like: interface Vlan1700 description Streaming2/Trust (an1) ip address 194.97.x.y 255.255.255.240 ip verify unicast source reachable-via rx allow-default ip flow ingress no mop enabled end Something is funny here... - so - how do I start figuring out why 1/20 of those packets are not being MLS/CEF switched? Oh well. I found the problem - someone leaked too many prefixes, and it's %MLSCEF-SP-7-FIB_EXCEPTION: FIB TCAM exception for IPv4 unicast, Some routes will be software switched. Dunno why it's showing *these* symptoms, affecting some interfaces more than others. But still I'm interested in finding out how to see what packets are not being MLS/CEF-switched, and why, for the next round of debugging :-) gert -- USENET is *not* the non-clickable part of WWW! //www.muc.de/~gert/ Gert Doering - Munich, Germany [EMAIL PROTECTED] fax: +49-89-35655025 [EMAIL PROTECTED] _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
