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https://www.juniper.net/us/en/local/pdf/app-notes/3500204-en.pdf
AC5K sflow configuration:
EX sflow:
user@switch# set collector <ip-address>
user@switch# set collector udp-port <port-number>
user@switch# set interfaces interface-name
user@switch# set polling-interval seconds
user@switch# set sample-rate number
Restrictions
Flow monitoring can be configured in version 5, version 8, or version 9 export mode. Up to eight version 9 collectors are supported in export mode
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