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• Two RSP module slots
• Two power supply slots
• One fan tray slot
Each network interface on a Cisco ASR 903 Router is identified by a slot number and a port number.
The figure below shows interface numbering in a Cisco ASR 903 Router.
Figure 46: Cisco ASR 903 Router Slot Numbers
RSP slot 1
1
RSP slot 0
2
Fan tray slot
3
Power supply slot 1
4
Power supply slot 0
5
Interface module slot 0
6
Interface module slot 1
7
Interface module slot 2
8
Interface module slot 3
9
Interface module slot 4
10
Interface module slot 5
11
Following is an explanation of the slot or port numbering:
• The numbering format is
Interface type slot or interface number
. Interface (port) numbers begin at
logical 0 for each interface type.
• Interface module slots are numbered from bottom to top, with logical interfaces on each module numbered
from left to right. Interfaces are hard-wired. Therefore, port 0 is always logical interface 0/0, port 1 is
always logical interface 0/1, and so on.
Cisco ASR 903 and ASR 903U Aggregation Services Router Hardware Installation Guide
45
Overview
Interface Numbering