Specifications

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Cisco AS5800 Operations, Administration, Maintenance, and Provisioning Guide
DOC-7810814=
Chapter 6 Provisioning
Split Dial Shelves
Leaving Split Mode
Split mode is exited when the dial-shelf configuration is changed by a no dial-shelf split slots
command. When the split dial-shelf line is removed, the router shelf will start using all of the TDM
timeslots. Feature boards that were not owned in split mode and are not owned by the other router will
be reset. Cards in slots that are owned by the other router will be reset, but only after the other DSC has
been removed or is no longer claiming the slots. The split-dial-shelf configuration should not be
removed while the second router shelf is still connected to the dial shelf.
When a router configured in split mode fails, all calls associated with the failed router are lost. Users
cannot connect back in until the failed router recovers and is available to accept new incoming calls.
However, the other split mode router shelf will continue to operate normally.
Potential Split-Dial-Shelf Problems
The system will behave as configured as soon as the configuration is changed. The exception is when
there is a misconfiguration, such as when one router is configured in split mode and the other router is
configured in normal mode, or when both routers are configured in split mode and both claim ownership
of the same slots.
Problems can arise if one of the two routers connected to a dial shelf is not configured in split mode, or
if both are configured in split mode and both claim ownership of the same slots. If the state of the second
router is known when the dial-shelf split slots command is entered and the command would result in a
conflict, the command is rejected.
If a conflict in slot ownership does arise, both routers receive warning messages until the conflict is
resolved. Any card in a slot that is claimed by both routers remains under the control of the router that
claimed it first, until you resolve the conflict by correcting the configuration of one or both routers.
Note that there can be slots that are not owned by either router (orphan slots). Cards in orphan slots
cannot boot up until one of the two routers claims ownership of the slot, because neither DSC will
download bootstrap images to cards in orphan slots.
Split-Dial-Shelf Show Commands
In normal mode, all show commands look and behave as they do in the current system. In split mode,
most show commands look and behave as they would in the current system if there were no cards in the
slots for which the other router has configured ownership. This is consistent with the view of a
split-dial-shelf configuration being basically two separate Cisco AS5800 universal access servers. A
router shelf cannot manage or even recognize cards in slots that it does not own. For example,
DSIP console and execute-on commands work only in owned slots.
There are, however, the following exceptions:
• The show dial-shelf clocks command still shows all configured clock sources, even those from
non-owned trunk cards. This is because only one DSC can provide the master clock, and it may need
to have backup clock sources configured from all trunk cards present (regardless of which DSC
owns them).
• To avoid confusion, the show dial-shelf command is extended so that when the router is in split
mode, show dial-shelf indicates both the router shelf is running in split mode and which slots the
router shelf owns. The status of any cards in any owned slots is shown, exactly as it is in the present
command. Thus, when in normal mode, show dial-shelf is unchanged from the current version.