21 Replies Latest reply on Aug 12, 2010 9:56 AM by Andy McBride

    Ip route-cache flow

      Hi All,

      i want configure netflow on cisco 837 and 877 for the netflow analyzer. my router wouldnt recognise the ip route-cache flow on the router on the interface on fastethernet. please help

        • Re: Ip route-cache flow

          Have you tried the netflow configurator? 


          Is it responding to the ip flow-cache and ip flow-export commands?

          • Re: Ip route-cache flow
            Andy McBride

            This should work on the 877s. The 837 will require NetFlow v9 config using ip flow ingress and ip flow egress commands at the (config-if) level. Make sure to configure netflow at the (config) level with

            Router(config)# ip flow-export version 9

            Router(config)# ip flow-export destination NTA server ip address 2055
            ip flow-cache active 1
              • Re: Ip route-cache flow

                thanks for the replies. i have a doubt now. router is 877 and its a site to site vpn and we have the vlans on the router. so ip route-cache flow command should be excuted on the vlans or on the fastethernet physical interface. on fe0 the ip route-cache command doesnt work. but on the vlan interface the command did work. please advise

                  • Re: Ip route-cache flow


                    Try this...

                    Global commands:

                    ip flow-cache timeout active 1
                    ip flow-export source Loopback1 (or the interface you want reporting to NTA)
                    ip flow-export version 5
                    ip flow-export destination <NTA IP> 2055
                    ip flow-top-talkers
                     top 20  
                     sort-by bytes

                    I typically don't use "ip route-cache flow," instead, try using "ip flow ingress" or "ip flow egress" on the physical interfaces.  All traffic flows through the physical interfaces, and you can capture all the conversations while limiting the resources necessary for collecting the data.

                    Here's the Cisco doc for reference, you probably already have this: http://www.cisco.com/en/US/docs/ios/12_1/switch/configuration/guide/xcdnfc.html

                    Hope this helps.


                      • Re: Ip route-cache flow

                         Hi Dwyane,

                        thanks.the main problem is my cisco router 877 wouldnt recognise the ip flow ingress or regress or route cache command on fe2 or fe0 which are the 2 physcial interface. the ip commands listed are below.there is no ip route cache or ingress listed.pls see below
                        interface IP configuration subcommands:
                         address             Set the IP address of an interface
                         ddns                Configure dynamic DNS
                         dhcp                Configure DHCP parameters for this interface
                         header-compression  IPHC options
                         rsvp                RSVP Interface Commands
                         rtp                 RTP parameters
                         vrf                 VPN Routing/Forwarding parameters on the interface

                  • Re: Ip route-cache flow

                    Hi Toms,

                    Not sure if you got this working, but I am using a Cisco 871, and can confirm that the Interface will take the ip flow command.

                    However the interface must also be configured.  For example on one of our FA interfaces, it is just setup as a Trunk port to a switch.  On that interface, the ip flow command is invalid.  On Interface 4, which we have configured as the WAN port via PPPOE, the ip flow command works.

                    You may want to look at how the interface is configured, to see if it will even report Netflow data.

                      • Re: Ip route-cache flow

                        Hi hutcha,

                        Thanks. we have used switch port  command on the interfaces,so we have vlan1 configured for the data. .ie fa0 as vlan1. so i have configured the netflow command on vlan1. the command wouldnt recognise on fa0.  on vlan1 its taken all the commands and when i look at the show ip flow and cache its giving the desired data but its not reaching the  nta server(nothing is blocking the port) so dont know what is happening.

                          • Re: Ip route-cache flow
                            Andy McBride

                            A couple of things you can do at this point.

                            Do a sho ip flow export on the router and make sure the IP address and port of the NetFlow collector are correct. Also check that the output indicates packets are being exported.

                            Next take a packet capture (Wireshark) from the Orion/NTA server interface and see if cflow packets are being received from the router. If they are then look at the indicated interface number and see if it is listed as interface 0. That could be an issue. If the sho command indicates that packets are properly being exported but Wireshark sees no cflow then something along the path to the NPM server is eating them.

                              • Re: Ip route-cache flow

                                HI Mcbridea,

                                thanks for the reply.

                                The router is showing its exporting. but analyzing the file capture, cant see anything recieved on the netflow server on that port.nothing is blocking that port though.

                                router#sh ip flow export
                                Flow export v5 is enabled for main cache
                                  Export source and destination details :
                                  VRF ID : Default
                                    Source(1)       10.xx.xx.1 (Vlan1)
                                    Destination(1)  10.xx..xx.14 (2055)
                                  Version 5 flow records
                                  151506 flows exported in 20577 udp datagrams
                                  0 flows failed due to lack of export packet
                                  74 export packets were sent up to process level
                                  0 export packets were dropped due to no fib
                                  0 export packets were dropped due to adjacency issues
                                  0 export packets were dropped due to fragmentation failures
                                  0 export packets were dropped due to encapsulation fixup failures