AT&T DS1/DMi/ISDN-PRI Generic 1 Maintenance Capabilities and Concerns, 6MAINTENANCE and Alarms

8-6MAINTENANCE AND ALARMS

GENERIC 1 MAINTENANCE CAPABILITIES AND CONCERNS

Generic 1 provides the same functional maintenance capabilities (such as error detection, error logging, error testing, and alarm reporting) as Generic 2. However, because of hardware and software differences and because Generic 1 uses the Manager rather than the Manager terminal, there are several user-perceived differences.

For example, Generic 1 maintenance uses the concept known as maintenance objects (MOs). Each type of circuit pack defines one or more MOs. Whenever an error is detected an entry is made in the error log for the particular MO. Furthermore, an alarm level (major, minor, or warning), whether the error was resolved as being on the circuit pack or off the circuit pack (such as a particular trunking facility), and the circuit pack name are all listed in the error log.

NOTE: Generic 1 MOs are similar to Generic 2 fault codes.

Generic 1 Maintenance Procedures

The hardware alarm report may be displayed at the Manager terminal by entering the display alarms command. The suggested order for doing maintenance is to clear the alarmed troubles first and then the non-alarmed troubles (that is, major alarms first, minor alarms second, and warnings last). When multiple alarms (of the same level) are on, they should be cleared in the order specified in chapter 8 of the Generic 1 Maintenance Manual.

For both DS1/DMI, and ISDN-PRIs, the DS1-BD MO should be investigated first as a means of resolving alarms associated with a DS1 circuit pack. This MO contains a series of tests, both nondestructive and destructive, which may be used to verify the alarms. Specifically, these tests are:

Test 138 Loss of Signal Alarm Inquiry — verifies the synchronization status of a DS1 link

Test 139 Blue Alarm Inquiry — verifies that the distant end is out of service

Test 140 Red Alarm Inquiry — checks the framing status of the link [for example, either out of frame, loss of frame alignment (LFA) alarm, or no red alarm detected]

Test 141

Test 142

Test 143

Test 144

Test 145

Test 146

Test 160

Yellow Alarm lnquiry — checks for a remote end out of frame or far end LFA

Major Alarm Inquiry

Minor Alarm Inquiry

Slip Alarm Inquiry

Misframe Alarm Inquiry

Translation Update — a destructive test that sends new or updated translations to a DS1

Remote-Loop Around — used as part of the process to isolate transmission facility failures

For ISDN-PRI facilities, the ISDN-TRK MO should be investigated to verify the service states of the B-channels. The ISDN-LNK MO may be used to verify correct operation of the D-signaling channel.