This section describes the basic configuration of PicOS switches in OVS (Open vSwitch) mode.
To configure the management IP address, users should use the picos_boot configuration script as described in PICOS Mode Selection. An alternative to using the configuration script is to manually edit the PicOS configuration file.
For accessing the switch through a user interface, instead of the management interface, some OpenFlow flows need to be configured to redirect management traffic to the control plane. This is needed only if the switch cannot be managed through the management interface.
For example, users need to add the following flows to access the switch inband. The bridge br0 has the MAC address c8:0a:a9:04:49:19.
Understanding OVS Components
The OVS as several components:
- ovsdb-server: A lightweight database server that provides switch level information (for example, information about switch ports).
- ovs-vswitchd: It is the core system component, which stores OpenFlow rules and performs flow based switching along with a companion Linux kernel module.
- openvswitch_mod.ko: It is a Linux kernel module doing most of the flow-based switching in PicOS OVS mode. This module is not loaded in the PicOS accelerated OVS, and is replaced by the ASIC (application-specific integrated circuit) for packet forwarding.
- CLI: The CLI (command-line interface) is used to control and manipulate other OVS components.
Understanding OVS CLI
The following three commands are used to control and monitor OVS:
- ovs-vsctl Commands: ovs-vsctl commands are used to control the ovsdb-server to create bridges, add interfaces, and configure interfaces.
- ovs-appctl Commands: ovs-appctl commands are used to control the ovs-vswitchd.
- ovs-ofctl Commands: ovs-ofctl commands are used to send OpenFlow queries. This can be used to manipulate the flows in ovs-vswitchd.
Each of those commands have a main page that can be viewed from the Linux shell on users' PicOS switch.