Reference Guide

Deriving Interface Indices
The Dell Networking OS assigns an interface index to each (configured and unconfigured) physical and
logical interface, and displays it in the output of the show interface command.
Dell#show interface fortyGigE 0/4
fortyGigE 0/4 is down, line protocol is down
Description: if_0/4 | if_forty
Hardware is DellForce10Eth, address is 74:86:7a:ff:6f:08
Current address is 74:86:7a:ff:6f:08
Pluggable media not present
Interface index is 51528196
[output omitted]
The interface index is a binary number with bits that indicate the slot number, port number, interface
type, and card type of the interface. Dell Networking OS converts this binary index number to decimal,
and displays it in the output of the show interface command.
Starting from the least significant bit (LSB):
• the first 14 bits represent the card type
• the next 4 bits represent the interface type
• the next 7 bits represent the port number
• the next 5 bits represent the slot number
• the next 1 bit is 0 for a physical interface and 1 for a logical interface
• the next 1 bit is unused
For example, the index 72925242 is 100010110001100000000111010 in binary. The binary interface index
for TeGigabitEthernet 1/21 of a 48-port 10/100/1000Base-T line card with RJ-45 interface. Notice that
the physical/logical bit and the final, unused bit are not given. The interface is physical, so represent this
type of interface by a 0 bit, and the unused bit is always 0. These 2 bits are not given because they are the
most significant bits, and leading zeros are often omitted.
To display the interface number, use the following command.
• Display the interface index number.
EXEC Privilege mode
show interface
Example of Deriving the Interface Index Number
To view the system image on Flash Partition A, use the chSysSwInPartitionAImgVers object or, to view the
system image on Flash Partition B, use the chSysSwInPartitionBImgVers object.
836
Simple Network Management Protocol (SNMP)