Open vSwitch (OVS) is the most popular open-source implementation of virtual switch on the Linux platform. As the today's data centers increasingly rely on the software-defined network (SDN) architecture, OVS is fastly adopted as the de-facto standard network element in data center's SDN deployments.
Open vSwitch has a built-in logging mechanism called VLOG. The VLOG facility allows one to enable and customize logging within various components of the switch. The logging information generated by VLOG can be sent to a combination of console, syslog and a separate log file for inspection. You can configure OVS logging dynamically at run-time with a command-line tool called ovs-appctl.
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