7210 SAS-D platforms with a 128MB flash can boot entirely new software releases. Older images cannot be used with these devices. 7210 SAS-D platforms with a 64MB flash can use any image. All 7210 SAS-D devices with a 128MB flash are shipped with the latest boot ROM. The system boot ROM, boot loader, and TiMOS image introduce the following checks to prevent use of older releases with this hardware:
If a user issues an admin reboot upgrade with an older boot.tim, the boot ROM detects it and fails to load the boot loader; instead, the boot ROM uses the golden bootstrap image, loads it for booting with the boot ROM, and loads the both.tim file.
If a user issues an admin reboot upgrade with an older boot.tim and older both.tim, the boot ROM detects it and fails to load the boot loader; instead, the boot ROM uses the golden bootstrap image and stops booting when the user specifies an earlier version of the both.tim, which the system cannot use. This process results in loss of management connectivity.
If a user issues an admin reboot upgrade with an older boot.tim, an older both.tim as primary, and a newer both.tim as secondary, the boot ROM detects it and fails to load the boot loader; instead, the boot ROM uses the golden bootstrap image. The boot loader checks the primary location for a compatible both.tim image, and because the image is an earlier version, the boot fails. The boot loader then checks the secondary location for a compatible both.tim image, and because the image is a newer version, the boot loader successfully boots the system.
The admin>update-golden-bootstrap CLI command does not update the golden bootstrap image with the boot.tim specified in the parameter value if the boot.tim is not a new image.