| 4.4. Boot Process | ||
|---|---|---|
 | Chapter 4. System Administration |  |
| 4.4. Boot Process | ||
|---|---|---|
| | Chapter 4. System Administration | |
The FB2500 contains internal Flash memory storage that holds two types of software :-
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 FB2500 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 I.
The green power LED has three defined states, as shown in Table 4.5 below :-
Table 4.5. Power LED status indications
| Indication | Status |
| Off | No AC power applied to unit (or possibly hardware fault) |
| Flashing with approximately 1 second period | Bootloader running / waiting for network connection |
| On | Main application software running |
After power-up, the normal power LED indication sequence is therefore to go through the ~1 second period flashing phase, and then - if at least one Ethernet port is connected to an active device - change to solid once the app is running.
From power-up, a FB2500 will normally boot and be operational in under five seconds.
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. The port LEDs on the panel on the opposite side to the physical ports also flash, in a clock-wise sequence.
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 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 6.4).
| |  | |
| 4.3. Software Upgrades |  | Chapter 5. Event Logging |