NDMP subtree backup of a qtree transfers significantly more data than qtree contains
Applies to
- ONTAP
- NDMP Subtree backup
Issue
- A NDMP subtree backup of a qtree, containing very little data (10 KB) backs up more data (tens of GB) than what exists in the qtree
- Dump Phase II time is observed to be unusually long for a subtree backup,as is Phase III
- By the end of the backup tens of GB of data are backed up
- The source of the additional data is not apparent when examining the backup log, ndmpd log, or the qtree itself
- In these backup log excerpts, the total count of inodes is zero, the number of directories is two, and the total size of all inodes is zero:
dmp Tue Jun 8 13:15:35 PDT 2021 /svm-name/vol1/qtree1(0) Log_msg (Total count of all - reg inodes: 0 lun inodes: 0 other inodes: 0 dirs: 2 nt dirs: 0 nt inodes: 0 acls: 0
dmp Tue Jun 8 13:15:35 PDT 2021 /svm-name/vol1/qtree1(0) Log_msg (Total size of all - reg inodes: 0 lun inodes: 0 other inodes: 0 dirs: 8 nt dirs: 0 nt inodes: 0 acls: 0
- Inconsistent with the inode stats, which are accurate, over 13 GB are backed up:
dmp Tue Jun 8 13:43:46 PDT 2021 /svm-name/vol1/qtree1(0) End (13476 MB)