With IPHost Network Monitor you can run simple snmp requests against a IBM device in your network.
ifIndex
if Index
1.3.6.1.2.1.2.2.1.1
A unique value, greater than zero, for each interface. It is recommended that values are assigned contiguously starting from 1. The value for each interface sub-layer must remain constant at least from one re-initialization of the entity's network management system to the next re-initialization.
Back to ibm_mainframe-Ifmib MIB page.
IPHost Network monitor allows you to monitor ifIndex on IBM device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring IBM Flex systems right now.