Brocade Flow Vision Administrators Guide (Supporting Fabric OS v7.3.0) - Manual (Page 65)

Activating Flow Generator flows
When a flow is activated, traffic is generated by the ingress port or source device for that flow and any
sub-flows associated with it as soon as all SIM ports and devices defined in the flow are online.
Activating a flow does not automatically clear the flow statistics for that flow; the existing statistic
counters resume counting using the resumed flow data. If you are activating a learned flow, the sub-
flows will be refreshed based on the first 39 Source ID-Destination ID pairs of SIM devices in the zone
database that are registered in the Name Server. A flow can be activated that includes SIM ports that
are either offline or that have not yet been created. If such a flow is activated, an alert message is
displayed, noting that the activated flow is not enforced.
To activate an inactive Flow Generator flow, complete the following steps.
1. Connect to the switch and log in using an account with admin permissions.
2. Enter flow --activate flow_name -feature generator.
The following example activates the Flow Generator flow named “Flow1”.
switch:admin> flow --activate Flow1 -feature generator
Automatic activation of a Flow Generator flow
Flow Generator automatically activates a generated flow under the following conditions:
• On flow creation, unless the flow is being created using the -noactivate keyword as part of the flow
command. Refer to Creating an inactive flow in Flow Generator on page 64 for information on this
procedure.
• On slot power-on, if the specified port belongs to the slot being powered on and the flow was active
when the slot was powered off.
• On a High Availability (HA) failover, or a HA reboot, if the flow was active when the HA event
occurred.
Learning in Flow Generator flows
To apply learning to a Flow Generator flow, use an asterisk inside of quotation marks ("*") to specify the
parameter to be learned.
When Flow Generator activates learned flows, it queries the Name Server database to identify source
and destination devices that are zoned together. These pairings are not automatically changed if either
member of the pair changes zones. If either member of the pair changes zones, you must deactivate
the flow and then reactivate it to use the new zone values. Flow Generator allocates the first 39 flows
per source ID to zoned destination IDs. The rest of the destination IDs are not tested. For learned flows,
zone enforcement is applied to both the source and destination SIM-Ports.
In the following example, the only flows that will be activated are the ones where the destination devices
share a zone with the source device (204000) and use ingress port 24. To view the data generated by
this flow, refer to
Viewing the output of a learned Flow Generator flow on page 66.
switch:admin> flow --create fgflow12 -feature generator -ingrport 24 -srcdev 0x204000
-dstdev "*"
Activating Flow Generator flows
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