4.4. Boot Process

4.4. Boot Process
	Chapter 4. System Administration

The FB6000 contains internal Flash memory storage that holds two types of software :-

main application software (generally referred to as the app)
a bootloader - runs immediately upon power-up, initialises the system, and then loads the app

It is possible for only one of these types of software, or neither of them, to be present in the Flash, but when shipped from the factory the unit will contain a bootloader and the latest factory-release application software. The FB6000 can store multiple app software images in the Flash, and this is used with an automatic fall-back mechanism - if a new software image proves unreliable, it is 'demoted', and the unit falls back to running older software. The show flash contents CLI command can be used to see what is stored in the Flash - see Appendix H.

4.4.1. LED indications

4.4.1.1. Port LEDs

Whilst the bootloader is waiting for an active Ethernet connection, the green and yellow LEDs built into the physical port connectors flash in a continual left-to-right then right-to-left sequence.

Note

The same port LED flashing sequences are observed if the app is running and none of the Ethernet ports are connected to an active link-partner. Note that the app continues to run, and the power/status LED will still be on solid.

When connected to an active link-partner, these flashing sequences will stop and the port LEDs will start indicating physical port status, with various status indications possible, controllable via the configuration (see Section 6.3).


4.3. Software Upgrades		Chapter 5. Event Logging