Datasheet

11-32
Cisco ONS 15454 SDH Reference Manual, R7.0
October 2008
Chapter 11 Circuits and Tunnels
11.16.4 Two Circuit Bridge and Roll
Note Create a Roll To Circuit before rolling a circuit with the source on Node 3 and the destination on Node 4.
A dual roll involves two cross-connects. It allows you to reroute intermediate segments of a circuit, but
keep the original source and destination. If the new segments require new cross-connects, use the Bridge
and Roll wizard or create a new circuit and then perform a roll.
Dual rolls have several constraints:
• You must complete or cancel both cross-connects rolled in a dual roll. You cannot complete one roll
and cancel the other roll.
• When a Roll To circuit is involved in the dual roll, the first roll must roll onto the source of the
Roll To circuit and the second roll must roll onto the destination of the Roll To circuit.
Figure 11-18 illustrates a dual roll on the same circuit.
Figure 11-18 Dual Roll to Reroute a Link
Figure 11-19 illustrates a dual roll involving two circuits.
Figure 11-19 Dual Roll to Reroute to a Different Node
Note If a new segment is created on Nodes 3 and 4 using the Bridge and Roll wizard, the created circuit has
the same name as the original circuit with the suffix _ROLL**. The circuit source is on Node 3 and the
circuit destination is on Node 4.
11.16.4 Two Circuit Bridge and Roll
When using the bridge and roll feature to reroute traffic using two circuits, the following constraints
apply:
• DCC must be enabled on the circuits involved in a roll before roll creation.
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Node 1
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D
Node 2
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Node 1
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Node 4Node 3
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New leg