Span Upgrades - Cisco ONS 15327 User Documentation

Span Upgrades

12.7 Span Upgrades
A span is the optical fiber connection between two ONS 15327 nodes. In a span upgrade, the
transmission rate of a span is upgraded from a lower to a higher OC-N signal but all other span
configuration attributes remain unchanged. With multiple nodes, a span upgrade is a coordinated series
of upgrades on all nodes in the ring or protection group in which traffic carried at a lower OC-N rate is
transferred to a higher OC-N. You can perform in-service span upgrades for the following ONS 15327
cards:
•
•
•
To perform a span upgrade, the higher-rate/long-reach optical card must replace the
lower-rate/intermediate-reach card in the same slot. If the upgrade is conducted on spans residing in a
BLSR, all spans in the ring must be upgraded. The protection configuration of the original
lower-rate/intermediate-reach optical card (two-fiber BLSR, UPSR, and 1+1) is retained for the
higher-rate/long-reach optical card.
When performing span upgrades on a large number of nodes, Cisco recommends that you upgrade all
spans in a ring consecutively and in the same maintenance window. Until all spans are upgraded,
mismatched card types will be present.
The Span Upgrade procedures require at least two technicians (one at each end of the span) who can
communicate with each other during the upgrade. Upgrading a span is non-service affecting and will
cause no more than three switches, each of which is less than 50 ms in duration. The Span Upgrade
procedures can also be used to perform span downgrades.
Cisco recommends using the Span Upgrade Wizard to perform span upgrades from OC-12 to OC-48.
Manual Span Upgrade procedures are mainly provided for OC-12 IR to OC-12 LR or OC-48 IR to
OC-48 LR span upgrades, or as error recovery for the wizard. The Span Upgrade Wizard and the Manual
Span Upgrade procedures require at least two technicians (one at each end of the span) who can
communicate with each other during the upgrade. Upgrading a span is non-service affecting and will
cause no more than three switches, each of which is less than 50 ms in duration.
Do not reach into a vacant slot or chassis while you install or remove a module or a fan. Exposed
Warning
circuitry could constitute an energy hazard.
Do not perform any other maintenance operations or add any circuits during a span upgrade.
Caution
Span upgrades do not upgrade SONET topologies, for example, a 1+1 group to a two-fiber BLSR.
Note
Note During the upgrade some minor alarms and conditions will be raised and will clear automatically.
There should be no service-affecting (SA, Major, or Critical) alarms. If any service-affecting alarms
occur, Cisco recommends backing out of the procedure.
BLSR Out of Sync alarms will be raised during span upgrades and will clear when the upgrade of all
nodes is complete; a four-node BLSR can take up to five minutes to clear all of the Out of Sync
alarms. Allow extra time for a large BLSR to clear all of the Out of Sync alarms.
Cisco ONS 15327 User Documentation, R3.3
12-12
OC-12 to OC-48
OC-12 IR to OC-12 LR
OC-48 IR to OC-48 LR
Chapter 12 Maintenance
June 2002