You can change existing service parameters. The changes are applied immediately. To display a list of services, use the show>service>service-using vpls command. Enter the parameter such as description SAP and then enter the new information.
*A:ALA-1>config>service>vpls# info
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description "This is a different description."
disable-learning
disable-aging
discard-unknown
local-age 500
stp
shutdown
exit
sap 1/1/5:22 create
description "VPLS SAP"
exit
exit
no shutdown
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*A:ALA-1>config>service>vpls#