7 Replies Latest reply: May 28, 2012 6:55 AM by mavturner RSS

Unable to query IP-ARP from Cisco Nexus 7000

khoapham

Hello,

 

I am not able to query for IP ARP from Cisco Nexus 7000. We have 2 of them.

Therefore, Search Device Tracker by IP Address no longer work.

When I go into UDT Job Status, I can see that UDT sees my switches as Layer 3 and Layer 2

 

We are using:

UDT version 2.0

Nexus 7010, version 6.1

2 VRF

The command to get the IP ARP is : "show ip arp vrf all"

 

Please advise.

 

Regards,

 
  • Re: Unable to query IP-ARP from Cisco Nexus 7000
    kaldawood

    define two snmp-server community strings for your vrfs

    Add your nexus to NPM twice with different IPs for the two communities then add them to UDT

    • Re: Unable to query IP-ARP from Cisco Nexus 7000
      khoapham

      I check the manual but couldnt find a way to define two snmp-server community strings for my vrfs

       

      Below is the respond from SolarWinds support

      There is a known bug in the Cisco Nexus code that does not respond to some of the MIBs that UDT polls. Are your Nexus devices using FEX?

      The two OIDs we poll IP Address information from are:

      ipNetToMediaTable 1.3.6.1.2.1.4.22
      ipNetToPhysicalTable 1.3.6.1.2.1.4.35

      You can use the UDT Compatibility Checker against these devices to see if they return any Layer 3 data. This application can be found under the installation path, for example, C:\Program Files (x86)\SolarWinds\Orion\UDT.

       

      And here what Cisco has to say about Solarwinds' respond

      I checked the supported device MIB list and it does show this MIB as included.

      ftp://ftp-sj.cisco.com/pub/mibs/supportlists/nexus7000/Nexus7000MIBSupportList.html

      It should inherit all the previous MIBS to newer codes of NXOS.

       

      So basically I'm hanging

      • Re: Unable to query IP-ARP from Cisco Nexus 7000
        kaldawood

        It works for me .. use the engineers toolset SNMP MIB browser to get that table

        RFC1213-MIB:ipAddrTable

        OID 1.3.6.1.2.1.4.20

         

        it will give you the ARP table for the VRF for which you specify the snmp community string in the query

         

        configure your nexus snmp sever:

        1- create the snmp context and map it to the second VRF :

        snmp-server context (context name) vrf (second vrf name)

        2- define the second community:

        snmp-server community second_community_string

        3- set the mib parameters for the second context

        snmp-server mib community-map (second_community_string) context (second vrf name)

         

        good luck

  • Re: Unable to query IP-ARP from Cisco Nexus 7000
    khoapham

    Well I just found another problem with this solution: You can only assign 2 IP addresses to a switch ==> Only works with 2 VRF or less

    Solarwinds does need to have a Cisco Nexus knowledge to change their software to make this right.

     

    Just to share with you I got replied from Cisco TAC as well:

    Snmpwalk by default queries Default-vrf only. If you want to query entries for a particular vrf, snmp-context has to be mapped to that vrf.

     

    1. e.g. To get the mgmt0 entries (vrf management), following needs to be configured on the N7k switch:

     

    snmp-server community public1 ro

     

    snmp-server context management vrf management

     

    snmp-server mib community-map public1 context management