Installation guide

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Cisco IGX 8400 Series Installation Guide, Release 9.3.3 and Later Releases
OL-1165-06
Chapter 3 Installing the IGX
Setting Up a UXM-E
Inverse Multiplexing over ATM on Trunks
An IMA lets you group physical T1 or E1 lines to form a logical trunk. A logical trunk consisting of
more than one T1 or E1 line supports connections with data rates that are much higher than the T1 or E1
rate. System software lets you specify IMA so that one or more physical lines within the logical trunk
can serve as backup if a line fails. IMA characteristics are as follows:
• All physical ports of an IMA trunk use the same line configuration.
• The node maintains a set of retained links for the IMA trunk to keep it active. The IMA trunk does
not fail unless the number of active trunks is less than the user-specified number of retained links.
• The IMA trunk can provide a clock source or clock path (see the cnftrk command). The first (the
lowest numbered) available physical line is used. If this line fails, the next available line within the
IMA provides the clock source or clock path.
• Full support for individual physical line alarms and statistics.
To specify the range of ports for an IMA trunk, you can use either Cisco WAN Manager or the
command-line interface (CLI). To define an IMA trunk on the CLI, use the uptrk command:
uptrk slot.start_port-end_port
For example, you could enter uptrk 8.1–4. Subsequently, you would refer to this logical trunk by using
only the slot number and first port number—8.1 in this example—when you use other commands, such
as addtrk, deltrk, cnftrk, and so on. Commands for viewing IMA information also include
dspportstats, dspphyslns, dsptrkcnf, dspfdr, dspnode, and dspphyslnstathist.
Adding an IMA Feeder Trunk
To add the UXM-E feeder trunk, you can use either Cisco WAN Manager or the CLI. To define an IMA
trunk on the CLI:
Step 1 Activate the trunk between the interface shelf and router by specifying the primary link and the IMA
group members of a UXM-E feeder trunk on an IGX routing node or an IGX feeder node:
uptrk slot.group-members
Step 2 Use the cnftrk command to configure the activated UXM-E feeder trunk:
cnftrk slot.primary link
Step 3 Use the addshelf command to add the feeder trunk to an IGX routing node:
addshelf slot.primary link shelf type
Note The routing node can be one of the following: IGX, BPX, or BPX-BXM/IMATM.