When a file in the pnfs filesystem is deleted the server stores information about is in the subdirectories of /opt/pnfsdb/pnfs/trash/. For dCache, the cleaner cell in the pnfsDomain is responsible for deleting the actual files from the pools asyncronously. It uses the files in the directory /opt/pnfsdb/pnfs/trash/2/. It contains a file with the pnfs ID of the deleted file as name. If a pool containing that file is down at the time the cleaner tries to remove it, it will retry for a while. After that, the file /opt/pnfsdb/pnfs/trash/2/current/failed.<poolName> will contain the pnfs IDs which have not been removed from that pool. The cleaner will still retry the removal with a lower frequency.