KNOWLEDGE BASE ARTICLE

Umango uses the SNMP protocol for device discovery. This enables Umango to perform an SNMP "walk" across the network and devices respond with their information. This is then populated into the devices list in the Umango UI. We also use SNMP when a user performs a "Forced Discovery" by performing an SNMP "probe" on the IP the user enters for discovery.

SNMP has its limitation - one of them being that an SNMP "walk" can only be performed within the same subnet as the query. An SNMP "probe" can be performed across accessible networks rather than just the same subnet (assuming the UDP ports 160/161 are open). This results in devices often not being discoverable when multiple NICs are enabled while they can still be discovered when a user forces discovery on a specific IP.

In addition, on servers that contain multiple NICs, Umango needs to know which NIC the devices should use to communicate back to the Umango server. Otherwise the wrong network can be assumed and the embedded apps cannot function properly.

Forcing the network can be done in any job's device sources screen. You select one or many devices and then (if there are multiple NICs on the server) an option to identify the network will display in a dropdown selection (see below).

It is important that this is done before the embedded apps are deployed as the return server address is part of the embedded app configuration. Once a device has had its network selected (using the process above) it does not need to be done again on other jobs - it is fixed across all jobs.