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New Member

Can anyone give me a packet run through

Of what happens when you use the TFTP transport protocol to gather configurations from a device? Does SNMP RW have to be enabled?

  • Network Management
Cisco Employee

Re: Can anyone give me a packet run through

Assuming you're wanting to know the flow when you request the configuration to be TFTP'd to a server using SNMP, then this is how it works.

1. The SNMP manager does an SNMP SET request (or multiple SET requests) of objects in the CISCO-CONFIG-COPY-MIB (thus SNMP read-write is required).

2. The agent (device) initiates a TFTP write-request to the specified TFTP server using the specified filename.

3. The write-request is processed by the TFTP server on udp/69. The TFTP server then responds to the agent's source UDP port with a new ephemeral UDP port on the server.

4. The agent begins to send data using its original UDP source port, and the new UDP destination port on the server.