We use Centera Viewer,

go to Commands >  Regenerations

If  there are regenerations in "stuck" state or regenerations have been  active for a longtime,

then this is an indication that we need to  check the cluster integrity.

If there are multiple stuck Regens, we need  to start from the oldest first.

In many cases the Regens are stuck due to  drive or node failure.

Every disk (except for those in same node  as failure) in cluster could potentially have mirror copy of blobs that  were on a failed disk, so therefore, a "regenerator" is created for each  type like performance regen,hyper regen and conditional regen.

Any response are welcome.