3Com NBX 100 Administrator's Manual page 215

CAUTION: Modifying a T1 group disconnects any calls in process on any
channels associated with the group.
Modifying a T1 Group
You may want to modify a Digital Line Card group to change its name,
Auto Extension assignments, or other parameters. When you modify a
group, the changes affect all the Digital Line Cards assigned to that
group. To modify a Digital Line Card group:
1 On the Digital Line Cards tab, from the Select Device Type drop-down list,
select one:
T1 Group List (for T1 DS1)
ISDN PRI Group List (for T1 ISDN PRI)
2 Click Apply.
3 Select the group that you want to modify.
4 Click Modify. The dialog box that appears depends on the Group List that
you selected either the T1 DS1 Modify Group dialog box or the T1 ISDN
PRI Modify Group dialog box.
5 Make the desired changes to the group parameters. See the Help for
details on each parameter.
6 Enable the On Line check box to bring the group on line.
7 Click Apply to effect the changes.
Changing T1 Group Membership
You can change the channel membership in a group to accommodate
changing needs.
To change group membership:
1 On the Digital Line Cards tab, select either T1 Group List (for DS1), or
ISDN PRI Group List (for ISDN PRI) from the Select Device Type drop-down
list and click Apply.
2 Select the group for which you want to change membership.
3 Click Membership. The dialog box that appears depends on the group list
you select.
4 To add a channel to the Member List, select the channel in the Non
Member List and click <<.
Configuring and Managing T1 Digital Line Cards 215