What should I know before upgrading my firmware to 6.4.0?
It is considered "best practice" to make a current backup of any and all critical/important data prior to performing any firmware update.
ReadyNAS OS 6: Firmware Upgrade Guide and Tips
ReadyNAS offers two ways to upgrade your firmware: ReadyNAS OS 6: Updating Firmware
Can I update my ReadyNAS directly to 6.4.0?
RN102 & RN104 systems running firmware older than 6.2.1 should first update to 6.2.5. Then update from 6.2.5 to 6.4.0.
RN2120 systems running firmware older than 6.2.1 should first update to 6.2.4. Then update from 6.2.4 to 6.4.0.
All other systems can update directly to 6.4.0.
My ReadyNAS reboots after attempting upgrade to 6.4.0 on RN100/RN2120 but it is stays on the same firmware, how do I resolve it?
There is a workaround for RN100/RN2120 units that will not upgrade due to a checksum issue. See the workaround for more information on this issue. This issue only affects RN100/RN2120 devices.
My ReadyNAS is stuck "Booting..." after the 6.4.0 firmware upgrade, how do I resolve it?
During the first boot after an upgrade to ReadyNAS OS 6.4.0, the ReadyNAS needs to complete a quota check. On some units such as the RN100/RN2120, this can be very time consuming and the unit may be in the "Booting..." process for quite some time while it completes the quota check. If your device appears in RAIDar, it is likely performing the quota check as expected and your ReadyNAS should not be restarted during this process. If your device does not appear in RAIDar, contact NETGEAR Support.
Additionally, we have had some other reports regarding ReadyNAS OS 6.4.0 where the chassis is stuck booting but the ReadyNAS does not proceed from this state. If neither the power LED nor the activity LED are blinking, you may be able to resolve your chassis issue by USB Recovering your ReadyNAS. For instructions on how to perform a USB Recovery Boot, see ReadyNAS OS 6: USB Recovery Tool.
In addition, you may find these threads posted by other community members helpful:
Stuck booting After automatic update
After Update firmware 6.4.0 device doesn't boot
[btrfs-cleaner] at 100% after upgrade
If [btrfs-cleaner] gets stuck at 100% after upgrade, this is likely due to the ReadyNAS performing a quota check. As mentioned previously, the ReadyNAS may take some time doing a quota check. This quota check should only run once after upgrading as long as it is able to complete successfully. Rebooting your chassis might cause the quota check to restart from the beginning. Please allow it some time to finish. Also, btrfs-cleaner is commonly invoked after Smart Snapshot Management prunes older snapshots. ReadyNAS commonly prunes older snapshots based on its snapshot schedule. If your ReadyNAS is restarting btrfs-cleaner every time you restart and consuming 100% CPU endlessly, or if the device is not behaving as notated here, please contact NETGEAR Support
6.4.1 maintenance release firmware fixes some of these issues