User manual
DEFINITY Enterprise Communications Server Release 6
Maintenance for R6vs/si 
555-230-127  
Issue 1
August 1997
Maintenance Object Repair Procedures 
Page 10-284CO-DS1 (DS1 CO Trunk) 
10
CO-DS1 (DS1 CO Trunk)
A DS1CO (central office) trunk provides a communications channel between the 
system and a central office switch through either a 1.544 Mbps or a 2.048 Mbps 
[G3iV2-386] DS1 link. A 24 channel DS1 link consists of 24 digital DS1CO trunks. 
A 32 channel DS1 link [G3iV2-386] consists of 30 digital DS1CO trunks. A 
DS1CO trunk can be used for both voice and data communication.
The DS1CO Trunk Maintenance provides a strategy in the system to maintain a 
CO trunk via a port on the DS1 Interface circuit pack. The TN767 and TN464 
[G3iV2-386] DS1 Interface circuit packs support the low level CO trunk signaling 
interfaces, ground-start and loop-start. This strategy covers the in-line errors log, 
initialization tests, periodic tests, system technician-demanded tests, and alarm 
resolution and escalation.
Three trunk service states are specified in the DS1CO trunk maintenance. They 
are: 
out-of-service
 in which the trunk is in a deactivated state and cannot be used 
for either incoming or outgoing calls; 
in-service
 in which the trunk is in an 
activated state and can be used for both incoming and outgoing calls; 
disconnect
 (ready-for-service) in which the trunk is in an activated state but can 
only be used for an incoming call. If the DS1 Interface circuit pack is 
out-of-service, then all trunks on the DS1 Interface circuit pack are also in the 
out-of-service state, and a Warning alarm is raised for each trunk.
Hardware Error Log Entries and Test to Clear 
Values
1. A Major alarm on a trunk indicates that alarms on these trunks are not downgraded 
by the set options command and that at least 75 percent of the trunks in this trunk 
group are alarmed.
MO Name (in 
Alarm Log)
Alarm 
Level Initial Command to Run Full Name of MO
CO-DS1 MAJOR
1
test trunk <grp/mbr> l DS1CO Trunk
CO-DS1 MINOR test trunk <grp/mbr> l DS1CO Trunk
CO-DS1 WARNING test trunk <grp/mbr> DS1CO Trunk
Table 10-94. DS1 CO Trunk Error Log Entries 
Error 
Type
Aux 
Data Associated Test
Alarm 
Level
On/Off 
Board Test to Clear Value
0
1
0 Any Any Any test trunk <grp>/<mbr>
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