2 Replies Latest reply on Aug 28, 2013 11:43 AM by bubbagump210

    NPM and RSTP

    bubbagump210

      We have redundant links in our network topology to handle switch failures, reboots, general L2 death etc. Of course to prevent loops and to reconfigure the topology we use RSTP. However, on any port that is in the Alternate state or in Designated state connected on the other side to a Backup or Alternate port, NPM logs 12 kajillion discards where as the switch shows things as fine. Of course by design RSTP has to set ports to discard at places. Is there some way to make NPM more intelligent so that it doesn't alert on the eleventy jillion discards a port in the Alternate state creates? Aka, can NPM be RSTP aware and only show us real discard problems?

        • Re: NPM and RSTP
          michal.hrncirik

          hi,

          we would like to introduce support for STP and its alternatives into NPM. I would be very interested to talk to you directly.

          But to your case, what you mean by saying "switch show things as fine"? Do You use some other software or using SNMP walk? In your case, you may do two things:

          1) you can modify your alert or trigger condition for this specific interfaces (first you may put there list of interfaces names which you know are typically involved in backup lines or you may extend the time of alert trigger

          2) you may stop monitoring statistics data on interfaces where you are interested only in UP/Down status.

            • Re: NPM and RSTP
              bubbagump210

              What I mean in that the switch shows as fine.... NPM shows that there are 100s of thousands of discards on my LAG interface which it is in the RSTP Alternate mode. However:

               

              console#show statistics port-channel 2

               

              Total Packets Received (Octets)................ 81323933264533

              Packets Received > 1518 Octets................. 9171396221    

              Packets RX and TX 64 Octets.................... 20092226      

              Packets RX and TX 65-127 Octets................ 12236514059   

              Packets RX and TX 128-255 Octets............... 1205761673    

              Packets RX and TX 256-511 Octets............... 611016325     

              Packets RX and TX 512-1023 Octets.............. 1050072784    

              Packets RX and TX 1024-1518 Octets............. 365087914     

              Packets RX and TX 1519-2047 Octets............. 4560732812    

              Packets RX and TX 2048-4095 Octets............. 1579521820    

              Packets RX and TX 4096-9216 Octets............. 8428284586    

               

               

              Total Packets Received Without Errors.......... 2047268600    

              Unicast Packets Received....................... 23504802018   

              Multicast Packets Received..................... 13241284      

              Broadcast Packets Received..................... 4061778       

               

              Total Packets Received with MAC Errors......... 0

              Jabbers Received............................... 0             

              Fragments/Undersize Received................... 0             

              Alignment Errors............................... 0             

              FCS Errors..................................... 0             

              Overruns....................................... 0             

              802.3x Pause Frames Received................... 0             

              Unacceptable Frame Type........................ 0             

               

               

              Total Packets Transmitted (Octets)............. 79193847585071

              Packets Transmitted > 1518 Octets ............. 1102175701 

              Max Frame Size................................. 9216          

               

              Total Packets Transmitted Successfully......... 2240011825

              Unicast Packets Transmitted.................... 19403600383

              Multicast Packets Transmitted.................. 10934560   

              Broadcast Packets Transmitted.................. 5346066  

               

              Total Transmit Errors.......................... 0

              FCS Errors..................................... 0          

              Underrun Errors................................ 0        

               

              Total Transmit Packets Discarded............... 0

              Single Collision Frames........................ 0             

              Multiple Collision Frames...................... 0          

              Excessive Collision Frames..................... 0             

               

              802.3x Pause Frames Transmitted................ 0             

              GVRP PDUs received............................. 0             

              GVRP PDUs Transmitted.......................... 0             

              GVRP Failed Registrations...................... 0             

              BPDU: sent 891345, received 369396

              Time Since Counters Last Cleared............... 29 day 4 hr 21 min 54 sec

               

              Or let's look at a port that is a member of this LAG:

               

              console#show statistics ethernet 1/g1

               

              Total Packets Received (Octets)................ 51950750484849

              Packets Received 64 Octets..................... 114410        

              Packets Received 65-127 Octets................. 2168141857    

              Packets Received 128-255 Octets................ 143403397     

              Packets Received 256-511 Octets................ 88874644      

              Packets Received 512-1023 Octets............... 77219881      

              Packets Received 1024-1518 Octets.............. 40281515      

              Packets Received > 1518 Octets................. 2741644433    

              Packets RX and TX 64 Octets.................... 7789997       

              Packets RX and TX 65-127 Octets................ 1731036410    

              Packets RX and TX 128-255 Octets............... 251803303     

              Packets RX and TX 256-511 Octets............... 120885208     

              Packets RX and TX 512-1023 Octets.............. 104322639     

              Packets RX and TX 1024-1518 Octets............. 47148728      

              Packets RX and TX 1519-2047 Octets............. 1034587013    

              Packets RX and TX 2048-4095 Octets............. 582678787     

              Packets RX and TX 4096-9216 Octets............. 2499928678    

               

              Total Packets Received Without Errors.......... 9554647434    

              Unicast Packets Received....................... 9552854372    

              Multicast Packets Received..................... 931568        

              Broadcast Packets Received..................... 861494        

               

              Total Packets Received with MAC Errors......... 0

              Jabbers Received............................... 0             

              Fragments/Undersize Received................... 0             

              Alignment Errors............................... 0             

              FCS Errors..................................... 0             

              Overruns....................................... 0             

              802.3x Pause Frames Received................... 29804         

              Unacceptable Frame Type........................ 1381349       

               

              Total Packets Transmitted (Octets)............. 11353610602304

              Packets Transmitted 64 Octets.................. 7675587

              Packets Transmitted 65-127 Octets.............. 3857861849

              Packets Transmitted 128-255 Octets............. 108399906

              Packets Transmitted 256-511 Octets............. 32010564

              Packets Transmitted 512-1023 Octets............ 27102758

              Packets Transmitted 1024-1518 Octets........... 6867213

              Packets Transmitted > 1518 Octets ............. 1375550045 

              Max Frame Size................................. 9216          

               

              Total Packets Transmitted Successfully......... 5415467922

              Unicast Packets Transmitted.................... 5407621423

              Multicast Packets Transmitted.................. 7846499    

              Broadcast Packets Transmitted.................. 0        

               

              Total Transmit Packets Discarded............... 0

              Single Collision Frames........................ 0             

              Multiple Collision Frames...................... 0          

              Excessive Collision Frames..................... 0             

               

              802.3x Pause Frames Transmitted................ 7590904       

              GVRP PDUs received............................. 0             

              GVRP PDUs Transmitted.......................... 0             

              GVRP Failed Registrations...................... 0             

              BPDU: sent 0, received 0

              Time Since Counters Last Cleared............... 29 day 4 hr 24 min 30 sec

               

              As you can see both of these interfaces look very clean, but NPM is showing tons of discards which I have to believe is because the port-channel 2 interface is in the RSTP Alternate state.