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SNMP v2c - custom port - cant connect to device



Hi guys,

i am setting up SNMP v2c but I need to use custom snmp port to connect as I have to set up destination nat for multiple devices to connect from outside over to inside nat. So every device will have 1 port higher: 16101, 16102 and so on.

now I have configured everything on the firewall and:

- the firewall works i can see traffic and data moving between inside host and prtg host ONLY when using snmpwalk - but when i add a device nothing happens not even connecting to firewall using prtg.

- on the firewall i can see traffic only when use snmpwalk but prtg - nothing, even they both on the same host with the same IP.

any ideas ?


prtg snmp snmpv2c v2c

Created on Jun 26, 2020 3:08:47 PM

1 Reply



Hello miklasz,

Did you test this snmpwalk while using the SNMP Tester?

Did you check if the correct port is configured in the device settings within PRTG?

Created on Jun 29, 2020 7:24:09 AM by  Timo Dambach [Paessler Support]

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