Storm Control

Storm control provides protection against excessive inbound BUM (broadcast, unknown unicast, multicast) traffic on layer 2 switch port interfaces, which can cause poor network performance.

Configure Storm Control

To configure storm control settings, you can either run NVUE commands or manually edit the /etc/cumulus/switchd.conf file.

The following command example enables broadcast storm control for swp4 at 400 packets per second (pps), multicast storm control at 3000 pps, and unknown unicast at 2000 pps.

cumulus@switch:~$ nv set interface swp4 storm-control broadcast 400
cumulus@switch:~$ nv set interface swp4 storm-control multicast 3000
cumulus@switch:~$ nv set interface swp4 storm-control unknown-unicast 2000
cumulus@switch:~$ nv config apply

The storm control settings require a switchd reload. Before applying the settings, NVUE indicates if it requires a switchd reload and prompts you for confirmation. When the switchd service reloads, there is no interruption to network services.

The following example command disables multicast storm control on swp4:

cumulus@switch:~$ nv unset interface swp4 storm-control multicast
cumulus@switch:~$ nv config apply

Edit the /etc/cumulus/switchd.conf file and uncomment the storm_control.broadcast, storm_control.multicast, and storm_control.unknown_unicast lines:

cumulus@switch:~$ sudo nano /etc/cumulus/switchd.conf
# Storm Control setting on a port, in pps
interface.swp4.storm_control.broadcast = 400
interface.swp4.storm_control.multicast = 3000
interface.swp4.storm_control.unknown_unicast = 2000

When you change the storm control settings, you must reload switchd with the sudo systemctl reload switchd.service command for the changes to take effect. The reload does not interrupt network services.

Show Storm Control Settings

To show the current storm control settings for a layer 2 interface, run the nv show interface <interface> storm-control command.

cumulus@switch:~$ nv show interface swp4 storm-control
                 applied  description
---------------  -------  ----------------------------------------------------------
broadcast        400      Configure storm control for broadcast traffic in pps
multicast        3000     Configure storm control for multicast traffic in pps
unknown-unicast  2000      Configure storm control for unknown unicast traffic in pps