Specifications

Configuring and Managing Cisco Access Servers and Dial Shelves
How to Configure Dial Shelves
DC-118
Cisco IOS Dial Technologies Configuration Guide
Verifying External Clock Configuration
To verify that the primary clock is running, enter the show dial-shelf clocks privileged EXEC command:
Router# show dial-shelf 12 clocks
Slot 12:
System primary is 1/2/0 of priority 202
TDM Bus Master Clock Generator State = NORMAL
Backup clocks:
Source Slot Port Priority Status State
-------------------------------------------------------
Trunk 2 1 208 Good Default
Slot Type 11 10 9 8 7 6 5 4 3 2 1 0
2 T1 G G G G G G G G G G G G
For more information on configuring external clocks, refer to the Cisco document Managing Dial
Shelves.
Configuring Dial Shelf Split Mode
This section describes the procedure required to transition a router from normal mode to split mode and
to change the set of slots a router owns while it is in split mode. Since the process of switching the
ownership of a slot from one router to the other is potentially disruptive (when a feature board is
restarted, all calls through that card are lost), a router shelf cannot take over a slot until ownership is
relinquished by the router that currently claims ownership, either by reconfiguring the router or
disconnecting that router or its associated DSC.
The dial shelf is split by dividing the ownership of the feature boards between the two router shelves.
You must configure the division of the dial shelf slots between the two router shelves so that each router
controls an appropriate mix of trunk and modem cards. Each router shelf controls its set of feature boards
as if those were the only boards present. There is no interaction between feature boards owned by one
router and feature boards owned by the other router.
Split mode is entered when the dial-shelf split slots command is parsed on the router shelf. This can
occur when the router is starting up and parsing the stored configuration, or when the command is
entered when the router is already up. Upon parsing the dial-shelf split slots command, the router frees
any resources associated with cards in the slots that it no longer owns, as specified by exclusion of slot
numbers from the slot-numbers argument. The router should be in the same state as if the card had been
removed from the slot; all calls through that card will be terminated. The configured router then informs
its connected DSC that it is in split mode, and which slots it claims to own.
In split mode, a router shelf by default takes half of the 2048 available TDM timeslots. The TDM split
mode is configured using the dial-shelf split backplane-ds0 command. (The dial-shelf split slot
command must be defined for the dial-shelf split backplane-ds0 command to be active.) If the
dial-shelf split slots command is entered when the total number of calls using timeslots exceeds the
number that would normally be available to the router in split mode, the command is rejected. This
should occur only when a change to split mode is attempted, in which the dial shelf has more than 896
calls in progress (more than half of the 1,792 available timeslots). Otherwise, a transition from normal
mode to split mode can be made without disturbing the cards in the slots that remain owned, and calls
going through those cards will stay up.