Flight Recorder

Table 1. Flight Recorder product support

Feature	Product	Release introduced
Flight Recorder for system health monitoring	5320 Series	Fabric Engine 8.6
	5420 Series	VOSS 8.4
	5520 Series	VOSS 8.2.5
	5720 Series	Fabric Engine 8.7

The Flight Recorder is a high level term for the framework in place on the switch to store both history and current state information for various kernel, system, and application data with minimal overhead to execution. This data can later be accessed on-demand when debugging systems issues to give engineers the best possible troubleshooting information. Functionally, the Flight Recorder consists of two elements; Persistent Memory and Always-on Trace.

The Persistent Memory feature stores information in volatile memory outside of any process. This feature provides information on crashes, errors, and outages that are not the result of a power failure. Persistent Memory data not saved to non-volatile storage before a power failure will be lost. Persistent Memory snapshots are taken when:

• a critical process stops functioning

• a process stops responding

• the hardware watchdog activates

• the user initiates a snapshot in the CLI

The Always-on Trace feature creates an ongoing, circular log of every trace call recently executed regardless of the trace level enabled by the user. The Always-On Trace feature uses circular logging, and therefore stores the most recent traces of the process.

Flight Recorder functionality is provided only through CLI. The following commands are used to make use of this feature:

• flight-recorder all {slot[-slot][,...]}

  The command creates a flight-recorder snapshot, trace and archive.

• flight-recorder archive {slot[-slot][,...]}

  This command creates a tarball of flight-recorder files, log files, and configuration files.

• flight-recorder snapshot {slot[-slot][,...]}.

  This command takes a snapshot of PMEM data.

• flight-recorder trace {slot[-slot][,...]}

  This command takes snapshot of always-on-trace data.