Kontron AT8902 - Manual (Page 87)

AT8902 Software Description
Page 4 - 20 AT8902 User Guide
• One Time Boot capability: After having updated the inactive kernel and root file system,
the new system has to be started by rebooting the board. In the case that the update has
installed an inoperable system which would cause the board to hang when booting, the
next board reset must restart the previous known good version of kernel and root file sys-
tem. This is achieved by programming the bootloader environment appropriately.
• Redundant bootloader environment sectors: When the system is updated, the bootloader
environment must be changed to be able to start the updated version. The bootloader
environment sector is stored twice in flash, one active version and one backup version in
case the active version is deleted during update due to power loss or similar errors. In
this case, the redundant environment would cause the bootloader to start the previous
known good version of kernel and root file system.
A software update of the Hub Board is done by performing the following steps:
1. Download kernel, initrd and application images into the appropriate slots of the flash mem-
ory. Ensure that the currently active images are not overwritten.
2. Select a configuration for base and fabric switch for the new software release. This can be
done by choosing the factory default or by storing the running system configuration into
flash.
3. Create a startup configuration by combining the slots with the update images and the con-
figuration slots for base and fabric switch.
4. Activate the selected startup configuration for One Time Boot.
5. Restart the board.
6. Activate the new startup configuration permanently
A software release for the AT8902 consists of three software packages for kernel, initrd and
application software. The packages are tar archives containing an image of the software and a
MD5 checksum file for consistency check. The name of the package file is arbitrary but the file
names in the archive must not be altered.
When performing a firmware update, the software packages are loaded from a remote TFTP
server in the first step. This is done by means of the frontpanel FE port of the Hub board. To
load a software package via TFTP into a specified slot, the CLI command ‘download’ is used:
(Base Fabric) #download kernel tftp://192.168.50.5/kernel.pkg B
Downloading image, this may take a while...
Successfully transferred kernel image tftp://192.168.50.5/kernel.pkg to slot 2
You may mark it active now and reboot to use the new kernel image.
(Base Fabric) #