Black Box LRU4240 - Manual (Page 78)

66 SALES: 0870 90 10 750 Dual Trunk E1 Router User’s Guide
Dual Trunk E1 Router
Loopback Tests
You can isolate sections of the Dual Trunk E1 Router to determine if it is defective. The problem is
normally in the network.
This section describes each of the loopback tests you can perform from the Dual Trunk E1 Router’s
front panel. The tests are:
• Loop NET 1/2
• Loop Payload
• Loop Up Remote and Loop Down Remote
Loop NET Test
The Loop NET test, illustrated in Figure 8-1 , verifies the operation of the E1 network and is
available only on full bandwidth.
This test loops the data received from the network back to the network. The data is regenerated
before it is looped back; however, the unit does not perform additional processing of the data. This
minimizes the impact of the unit during the test so that network problems can be isolated.
This test can loop Net1, Net2, and All Nets.
DRAM CRC Error CRC of RAM copy of executing code failed.
Flash Boot Error CRC of flash boot code failed.
Flash Loader Error CRC of flash factory loader failed.
Net Error Pattern test failed.
Flash Write Error Flash write test failed.
NOTE: No test is 100% complete and a small portion of the network will remain
untested. Your unit may allow only one active loopback at a time.
NOTE: In the figures that illustrate the available tests, the path for only one Port
(Link) is shown, to prevent overly confusing drawings. If the test is also being run on
the second port, its path will be similar to that shown in the figure.
Table 8-1 Self Test Indicators
Indicators Description