Sentinel: What should I do if my Sentinel won't boot?
Occasionally Sentinel may get into a state that it sticks on the opening splash screen displaying the message Loading Operating System but fails to complete the boot process. If a power cycle does not fix this then the firmware needs reprogrammed.
The following steps detail how to reprogram the firmware from an external USB stick for Sentinels with a serial number greater than 300000.
Create a folder called rrrecoverydir on a USB stick formatted to FAT32.
Download the latest Sentinel firmware from the Support Portal, unpack the sentinel_fw_Rx.x.x.tar file. As an example the contents of the sentinel_fw_R15.0.0.tar file are shown.
Unpack the sentinel_fw_v2.15.0.0.6698-20211208.tar archive
Insert the USB stick into the Sentinel unit and power up. The firmware will be restored and the Sentinel should boot.
NOTE: The process may prompt to update the firmware on the PTP cards.Remove the USB stick before re-boot to prevent the recovery process from starting over again. It is also advisable to delete the rrrecoverydir directory from the USB stick.