When ReadyNAS firmware is upgraded, snapshots can become invisible, losing much space. To fix that:
- Turn on SSH, in System / Settings / Services.
- Using putty, SSH to root@nas , where “nas” is the IP of the NAS, using the admin password.
- Do this:
touch /.force_snapshots_upgrade systemctl restart readynasd
- The GUI will report upgrade in progress. Wait for it.
- We have now fixed it so we can do things to the snapshots. Let’s make them visible in the filesystem. Browse to Shares, click on the share name (often Backup), click the gear icon on the right, and check Allow Snapshot Access, Apply and OK.
- We can now see them at \\NAS\Backup\snapshots. If we create a blank directory on the Windows server’s hard drive, say C:\B, and do the following, we will wipe all of the snapshots on that share and begin recovery of all of the space:
ROBOCOPY C:\B \\NAS\Backup\snapshots /MIR /R:1 /W:1
Full recovery of the space actually takes a bit more, there are automatic elements which initiate after the above is done, and also after the next step is done. - Then we run a Balance operation which Netgear recommends. Browse to System, then Volumes, and then click the Gear icon inside the NAS object, and choose Balance. This will take a while, and more space will be recovered. A weekly Scrub and Balance are both recommended. Scrub actually takes longer.
References:
https://kb.netgear.com/30068/ReadyNAS-OS-6-SSH-access-support-and-configuration-guides