Cisco BPX 8600 Series, Руководство по установке и настройке

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Cisco BPX 8600 Series Installation and Configuration
Release 9.3.0, Part Number 78-10674-01 Rev. D0, July 2001
Chapter 29 Troubleshooting
Troubleshooting the BPX Switch
Loopback Tests
Various loopback paths can be set up to help diagnose transmission problems. These rely on using
external test equipment to provide the source of a test signal.
The available loopback commands are listed in Table 29-4.
You set up a local loopback path (LL) in the local node at the PAD card (FRP) associated with the port
or connection to be tested. You then apply a test signal to the input. This passes through the associated
Interface Card (FRI), is sent to the Frame Relay PAD card (FRP) over the system bus where it is looped
back towards the input. This tests the cabling and the local node processing of the signal.
A remote loopback path (RL) is set up in the remote node also at the PAD card (FRP). But, in this case,
the signal travels over the network and through the remote node processing equipment but does not
include the remote node Interface Card (FRI) or associated cabling. These components would be tested
using another local loopback at the remote node.
The external loopback command finds limited use in data applications where an external data interface
unit (DSU or CSU) is attached to the local node data interface card, illustrated by the SDI card in . The
local node transmits the appropriate loopback codes out the circuit line towards the external device and
then sets up the appropriate loopback path.
Display Slot Alarms (dspslotalms) Displays any alarms associated with the slots in a BPX node.
Display Trunk Errors (dsptrkerrs) Displays any data errors associated with the network trunks connected to a node.
Table 29-3 System Troubleshooting Commands Available (continued)
Command Description
Table 29-4 System Loopback Tests
Command Description
Add Local Loopback
(addloclp)—frame relay port Adds a loopback path at the frame relay port from the transmit side back to the
receive side at the local node.
Add Local Loopback
(addloclp)—frame relay connection Does the same as above only for an individual frame relay connection.
Add Local Loopback (addloclp)—data Adds a loopback path at the synchronous data port from the transmit side back to
the receive side at the local node.
Add Local Loopback
(addloclp)—voice Adds a loopback path for an individual voice channel on a circuit line at the local
node.
Add Remote Loopback
(addrmtlp)—frame relay port Adds a loopback path at the frame relay port from the transmit side back to the
receive side at the remote node.
Add Remote Loopback
(addrmtlp)—frame relay connection Does the same as above only for an individual frame relay connection.
Add Remote Loopback
(addrmtlp)—data Adds a loopback path at the synchronous data port from the transmit side back to
the receive side at the remote node.
Add Remote Loopback
(addrmtlp)—voice Adds a loopback path for an individual voice channel on a circuit line at the remote
node.
Add External Loopback
(addextlp)—data Activates a near end or far end loopback on an external device, such as a DSU,
connected to a synchronous data port.