Dear Primoz it is really a weird problem but it needs more isolation steps , regarding the CRC point CRC are counted at the fabric interface between LC and Fabric and that is why it is not shown at the interface counters , you can check CRC errors according to th below cisco links
http://www.cisco.com/warp/public/63/output_shcontfia.html http://www.cisco.com/warp/public/108/hwts_12000_22281.html#ts_switchfabr then we can look the processes utilizes the line cards CPU best regards Abo Zaid On 11/30/07, Primoz Jeroncic <[EMAIL PROTECTED]> wrote: > > Hi > > I have some weird problems on one of our STM-4 links. From time to time > about 5-7 packets get lost on this link. It doesn't happen every > X minutes/hours but randomly, and always with 5-7 packets in row. There's > no CRC, input or output errors on any of ports, and also our carrier > is trying to tell me, everything is fine on their link. Overall, packet > loss is about 0.2 to 0.5% during longer period (1 day or more). > > So I went to check with routers. On both sides we are running GSR with > 4 Port Packet Over SONET OC-12c/STM-4 SM line cards. So when I went to > check, I found out, on one side, LC processor has 50-60% utilization, > while on other it has 3-4% utilization (on both sides it's constantly > at such percentage). I still don't think this packet loss would be > connected to "high" (50-60%) utilization, since if it would be, I would > have this packet loss contantly, not just few packets every few hours. > And it's also not fully utilized port either. Average throughput is > about 400Mbps, while peaks never go over 500Mbps. > > So now I have 2 questions. First... does anyone have any idea what could > be reason for such packet loss? > > And second... And idea why one LC would be at 3-4%, while other would > be at 50-60%? Both LCs are same, both routers are same, and even config > on both LCs is same... see below: > > Diags are same for both, except one is in slot 1, while other is in slot > 6: > > SLOT 1 (RP/LC 1 ): 4 Port Packet Over SONET OC-12c/STM-4 Single Mode > FRU: Linecard/Module: 4OC12/POS-IR-SC-B= > Route Memory: MEM-GRP/LC-256= > Packet Memory: MEM-LC1-PKT-256= > L3 Engine: 2 - Backbone OC48 (2.5 Gbps) > DRAM size: 268435456 bytes > FrFab SDRAM size: 134217728 bytes, SDRAM pagesize: 8192 bytes > ToFab SDRAM size: 134217728 bytes, SDRAM pagesize: 8192 bytes > > > Config on port: > Location 1 (utilization 50-60%): > interface POS6/0 > bandwidth 622080 > ip address x.x.x.1 255.255.255.252 > no ip redirects > no ip unreachables > no ip directed-broadcast > encapsulation ppp > ip route-cache flow sampled > load-interval 30 > tag-switching mtu 1546 > tag-switching ip > crc 16 > clock source internal > pos framing sdh > pos flag s1s0 2 > > Location 2 (utilization 3-4%) > interface POS1/0 > bandwidth 622080 > ip address x.x.x.2 255.255.255.252 > no ip redirects > no ip unreachables > no ip directed-broadcast > encapsulation ppp > ip route-cache flow sampled > load-interval 30 > tag-switching mtu 1546 > tag-switching ip > crc 16 > clock source internal > pos framing sdh > pos flag s1s0 2 > > Only difference betwen boxes is IOS. On Location 1, we are running > service provider ios 12.0(30)S5, while on Location 2 we are running > 12.0(26)S5. > > And help, tips, suggestions are more then welcome :) > > Thanks for help. > > Have fun, > Primoz Jeroncic > Support - IP Connectivity & Routing > ------------------------------------------------------------------- > Softnet d.o.o. tel: +386 1 562 31 40 | > Borovec 2 fax: +386 1 562 18 55 | 1 + 1 = 3 > 1236 Trzin primoz(at)softnet.si | for larger values of 1 > Slovenija http://flea.softnet.si/ > ------------------------------------------------------------------- > > _______________________________________________ > cisco-nsp mailing list [email protected] > https://puck.nether.net/mailman/listinfo/cisco-nsp > archive at http://puck.nether.net/pipermail/cisco-nsp/ > _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
