Host not SNMP discovering in Smarts

Products

• VMware Smart Assurance

Issue/Introduction

• How to execute a packet capture in Linux to troubleshoot Smarts polling or discovery errors?
• How to generate a tcpdump in Linux to troubleshoot Smarts polling or discovery errors?
• Receive Smarts IP/Smarts NPM/Smarts MCAST polling or discovery errors in Linux environment.
• snmpwalk of device is successful but does not discover in Smarts.

Environment

Smarts - 10.1.x

Resolution

The following are some examples of how to run a tcpdump of a Linux network cap trace that can be used to troubleshoot Smarts IP/Smarts NPM/Smarts MCAST polling or discovery errors.

• Executing tcpdump from Smarts server against a problem device
  The following shows the command syntax for a basic tcpdump written to a file (-w) called <IP Address>.cap, executed from the Smarts server against a device (host) that has demonstrated a Smarts polling or discovery failure:

         tcpdump -i any host #.#.#.# and port 161 -w test.pcap

         (where #.#.#.# is the IP address of the device)

 

• Other examples:

        tcpdump  w file.cap (use -i to specify interface, -i eth0 to specify eth0 interface) (-s0 captures full 65535 bytes in packet)

        tcpdump -w test.pcap src #.#.#.# or dst #.#.#.# (capture src (source) and dst (destination) packets from IP address #.#.#.#.)

        tcpdump -w test.cap src port 39478 or dst port 161

        tcpdump -w test.cap  port 39478

 

• Reading the packet capture file
  To read packet capture files, you can use following command or move pcap to Windows system with the Wireshark app loaded:

tcpdump -nnr test.pcap (read)