Understanding How Devices Are Configured to Send SNMP Traps to Junos Space
Devices discovered in Junos Space are automatically configured to send SNMP traps to Junos Space.
The trap destination IP address that is configured on devices depends on whether a separate device management interface (eth3) is used on the node on which network monitoring is currently running. If the node uses the eth3 interface for device management, then the discovered devices are configured with the eth3 IP address. Otherwise, the discovered devices are configured with the virtual IP (VIP) address of the Junos Space cluster. If the VIP is configured as the trap destination, you do not need to reconfigure the trap destination on managed devices after a VIP failover because network monitoring will be started automatically on the node that currently owns the VIP and the node will start receiving the traps. However, if the eth3 IP address is configured as the trap destination, you must reconfigure all devices when a VIP failover occurs. This will be done automatically as part of the startup process of network monitoring on the second HA node. When network monitoring comes up on the new node, the trap destination on all managed devices will be automatically reconfigured to be the eth3 IP address for this node.
Automatic reconfiguration is not possible for devices whose connection with Junos Space is down at the time of the network monitoring failover. If there are any such devices, network monitoring stops receiving traps from these devices after the failover, and you will need to manually change the trap destination on these devices to the eth3 IP address of the node where network monitoring is currently running.