Limiting the usage of hardware resources


openflow limit {policy-engine-usage | ip-ctrl-table-usage | multiport-filter-usage} <max-percentage>

Maximum percentage of policy engine resources used by OpenFlow.


Maximum percentage of IP control table resources used by OpenFlow.


Maximum percentage of the multiport-filter resources used by OpenFlow.

You can limit the OpenFlow usage of policy engine resources, ip control table, and multiport filters so that other functions that use the same resources are not impacted severely.

The limit can be set only when OpenFlow is disabled globally.


Specifying 0% allocates no resources for OpenFlow.

By default, the OpenFlow policy engine resource usage is set at 50% to avoid oversubscribing resources and impacting performance. The policy engine resource can use Access Control Lists, Quality of Service, Identity Driven Management, Virus Throttling, Mirroring, Policy Based Routing, and other features in addition to OpenFlow.


The maximum percentage is not a guaranteed percentage but a maximum allowed limit.

To increase the number of flows beyond the default 50% setting, use the above OpenFlow limit policy-engine-usage command. If all policy engine resources are in use, OpenFlow rules are no longer added in hardware and the switch denies attempts to configure ACLs with the CLI. See “Monitoring Resources” in the latest Management and Configuration Guide for your switch.

Default: 50%; Range: 0 - 100%


Resource usage can be set only when OpenFlow is disabled.


switch(openflow)# limit multiport-filter-usage
<0-100>                Enter a number.

switch(openflow)# show openflow multiport-filter-limit

Total Multiport Filters: 1039

              Filters      Filters       Filters
Features      Allocated    Used          Free
-----------   ----------   ------------  --------------
OpenFlow      519          1             518