Dell C1048P Port Extender Networking Configuration Guide for the C9000 Series - Page 1068

The interface index is a binary number with bits that indicate the slot number, port number, interface type, and card type of the interface. The system converts this binary index number to decimal, and displays it in the show command output. Figure 128. Example of Assigning Interface Index Numbers Starting from the least significant bit (LSB) in the preceding figure: • The first 14 bits represent the card type of a physical interface or the interface number of a logical interface. • The next 4 bits represent the interface type. • The next 12 bits represent the slot and port numbers. • The next bit is 0 for a physical interface and 1 for a logical interface. • The last next is unused. The Slot-Port Number value is derived from the slotId and portId parameters as follows: slotPortNum = ((slotId +1) * IFM_IFINDEX_MAX_PORTS_PER_SLOT + portId). The IFM_IFINDEX_MAX_PORTS_PER_SLOT value is 192 (10G). For backward compatibility, the IFM_IFINDEX_MAX_PORTS_PER_SLOT value is 128 on other Dell Networking switches. The slotId value is derived as follows: slotId = (slotPortNum / IFM_IFINDEX_MAX_PORTS_PER_SLOT) -1. The portId value is derived as follows: portId = slotPortNum % IFM_IFINDEX_MAX_PORTS_PER_SLOT. For example, the interface index 51528196 for the FortyGigE 0/4 port is 0000 0011 0001 0010 0100 0010 0000 0100 in binary format as shown in the following figure. Figure 129. Interface Index Number Assigned to FortyGigE 0/4 Port In this example, if you start from the least significant bit on the right: • The first 14 bits (00001000000010) identify a line card. • The next 4 bits (1001) identify a 40-Gigabit Ethernet interface. Simple Network Management Protocol (SNMP) 1068