SNMP node usage example (MOXA EDS-518A)
Simple example how snmp nodes can be used. Look from the MIB file OID address that corresponding switch uses. You have to add parser (function node) to read actual content from the payload.
[{"id":"75c5f1c6.56241","type":"snmp","host":"192.168.77.13","community":"public","version":"1","oids":"1.3.6.1.2.1.2.2.1.8.1","name":"Port01 (get OK)","x":344.89581298828125,"y":113.88888549804688,"z":"274f3737.bf0f18","wires":[["d085f9e6.016858"]]},{"id":"e5a4f80b.8bfa38","type":"inject","name":"Test","topic":"","payload":"","payloadType":"none","repeat":"","crontab":"","once":false,"x":175.8958282470703,"y":113.88888549804688,"z":"274f3737.bf0f18","wires":[["75c5f1c6.56241"]]},{"id":"d085f9e6.016858","type":"debug","name":"","active":true,"console":"false","complete":"payload","x":573.8957977294922,"y":115.88888549804688,"z":"274f3737.bf0f18","wires":[]},{"id":"9ff12da9.82a26","type":"inject","name":"Test","topic":"","payload":"","payloadType":"none","repeat":"","crontab":"","once":false,"x":160.89581298828125,"y":174.88888549804688,"z":"274f3737.bf0f18","wires":[["ff62d996.816d78"]]},{"id":"867ded10.3458c","type":"debug","name":"","active":true,"console":"false","complete":"false","x":595.8957366943359,"y":174.88888549804688,"z":"274f3737.bf0f18","wires":[]},{"id":"ff62d996.816d78","type":"snmp","host":"192.168.77.13","community":"public","version":"1","oids":"1.3.6.1.2.1.2.2.1.8.1,\n1.3.6.1.2.1.2.2.1.8.2,\n1.3.6.1.2.1.2.2.1.8.3,\n1.3.6.1.2.1.2.2.1.8.4,\n1.3.6.1.2.1.2.2.1.8.5,\n1.3.6.1.2.1.2.2.1.8.6,\n1.3.6.1.2.1.2.2.1.8.7,\n1.3.6.1.2.1.2.2.1.8.8","name":"Ports 1-8 (table OK)","x":353.8957824707031,"y":174.88888549804688,"z":"274f3737.bf0f18","wires":[["867ded10.3458c"]]},{"id":"21b3235e.e5379c","type":"comment","name":"net-snmp","info":"","x":316.89576721191406,"y":28.888885498046875,"z":"274f3737.bf0f18","wires":[]},{"id":"947eb302.1f486","type":"comment","name":"node-red-contrib-snmp","info":"","x":358.89576721191406,"y":67.88888549804688,"z":"274f3737.bf0f18","wires":[]},{"id":"68d042a.123f7bc","type":"snmp subtree","host":"192.168.77.13","community":"public","version":"1","oids":"1.3.6.1.2.1.2.2.1.8","name":"Subtree","x":326.89581298828125,"y":233.88888549804688,"z":"274f3737.bf0f18","wires":[["209eddb8.540ba2"]]},{"id":"397962ad.644eee","type":"inject","name":"Test","topic":"","payload":"","payloadType":"none","repeat":"","crontab":"","once":false,"x":158.89581298828125,"y":232.88888549804688,"z":"274f3737.bf0f18","wires":[["68d042a.123f7bc"]]},{"id":"209eddb8.540ba2","type":"debug","name":"","active":true,"console":"false","complete":"payload","x":595.8957977294922,"y":230.88888549804688,"z":"274f3737.bf0f18","wires":[]},{"id":"beaddfdd.d8557","type":"inject","name":"Test","topic":"","payload":"","payloadType":"none","repeat":"","crontab":"","once":false,"x":153.89581298828125,"y":287.8888854980469,"z":"274f3737.bf0f18","wires":[["9251c612.173468"]]},{"id":"bc259f1e.7e5ea","type":"debug","name":"","active":true,"console":"false","complete":"payload","x":590.8957977294922,"y":285.8888854980469,"z":"274f3737.bf0f18","wires":[]},{"id":"9251c612.173468","type":"snmp walker","host":"192.168.77.13","community":"public","version":"1","oids":"1.3.6.1.2.1.2.2.1","name":"Walker","x":339.8958282470703,"y":287.8888854980469,"z":"274f3737.bf0f18","wires":[["bc259f1e.7e5ea"]]},{"id":"93ab7e15.044be","type":"comment","name":"Port status","info":"Value == 1 # Port is connected\nValue == 2 # Port is not connected\n","x":765.5148315429688,"y":115.54073333740234,"z":"274f3737.bf0f18","wires":[]},{"id":"b8b080f4.8398c","type":"comment","name":"Walker","info":"This wil take time to iterate and\ndump the whole OID table.","x":329.51483154296875,"y":341.54073333740234,"z":"274f3737.bf0f18","wires":[]},{"id":"6fc78485.5f542c","type":"comment","name":"Subtree","info":"Faster to use than multiple single requests.","x":791.5148315429688,"y":230.54073333740234,"z":"274f3737.bf0f18","wires":[]}]