Users may sometimes see false alerts while monitoring SRX5000 Series devices by using the Simple Network Management Protocol (SNMP). They may also observe that incorrect Routing Engine 1 values are returned to SNMP Manager.

This article explains the reason for such behavior, and indicates what must be done to work around the issue.

Below is an example output of CPU usage for Routing Engine 0 and 1.

Note: This output is confirmed on SRX5800 with Junos OS 15.1X49-D110.4.

root@SRX5800> show snmp mib walk jnxOperatingDescr.9
jnxOperatingDescr.9.3.0.0 = node1 Routing Engine 0
jnxOperatingDescr.9.4.0.0 = node1 Routing Engine 1

root@SRX5800> show snmp mib walk jnxOperatingCPU.9
jnxOperatingCPU.9.3.0.0 = 3
jnxOperatingCPU.9.4.0.0 = 3 <<< RE1 returns same value as RE0.

Routing Engine 1 on SRX 5K is used only for control link redundancy and does not work for as the redundant Routing Engine.

For more information about the dual control link for SRX 5K devices, refer to Understanding Chassis Cluster Dual Control Links .

Due to this, the Junos OS process does not run on Routing Engine 1 and the SRX device returns incorrect values when MIB relating to Routing Engine 1 is queried from SNMP Manager.

This is as per design.

It is recommended to ignore Routing Engine 1's value that is retrieved by SNMP or to stop monitoring Routing Engine 1 as a workaround for the issue.

If, for some reason, you need to check Routing Engine 1's status, access Routing Engine 1 by using a console connection and issue a BSD command such as the " top " command: root@% top