3Com SuperStack 3 NBX, Administrator'S Manual

Page: 270 / 496

270 C
HAPTER
3: D
EVICE
C
ONFIGURATION
Some telephone companies offer Partial E1 lines as their standard
offering and provide fully implemented E1 lines only if you make a
specific request. If you are unaware of this, outbound calls using the E1
line may fail because the system places outbound calls using high
numbered channels first, and a Fractional E1 typically has the lower
numbered channels implemented.
In the Span Status dialog box, under Details of last five calls , if you see the
error message REQ_CHANNEL_UNAVAIL , determine if the error is caused
by a Partial E1:
1 Remove the highest numbered channel from service (set it to offline in
the Modify Channel dialog box) and retry the outbound call.
2 Continue to remove channels until an outbound call succeeds.
3 When the first outbound call succeeds, the highest numbered channel
still in service represents the number of active (provisioned) channels in
the Partial E1.
4 Create two groups. Put all of the active channels in one group, and all of
the inactive channels in the other. Mark the active group “online” and
the inactive group “offline.”
Modifying Audio Controls
In a normal environment, do not change the Audio Controls from their
default settings. If you have an issue with sound quality and you cannot
resolve it using the volume controls on the NBX Telephones, contact your
technical support representative.
CAUTION: Do not change your Audio Controls settings unless you are
instructed to do so by a qualified support representative.
Adding or Modifying
an E1 Group
A digital line card group is one or more E1channels that are assigned the
same characteristics, such as Channel Protocol. This section describes
how to perform these actions:
■
Adding an E1 Group
■
Modifying an E1 Group
■
Changing E1 Group Membership
■
Removing an E1 Group
CAUTION: Modifying an E1 group disconnects any calls in process on any
channels associated with the group.