How are NDMP backup logs of FlexGroup different than FlexVol logs?

Applies to

• ONTAP 9.7 and later
• NDMP FlexGroup

Answer

• Unlike a FlexVol, which resides on one node, a FlexGroup and its constituent volumes may reside across multiple nodes
• For FlexGroup backups, a backup log will reside on each node hosting a FlexGroup constituent 
• Unlike a FlexVol backup log, the "master" FlexGroup backup log contains master and member messages
• The "master" backup log resides on the node hosting the *__0001 flexgroup constituent
• The master lines in the backup log capture the NDMP session number, options, all dump phases, as well as messages and stats for the flexgroup volume
• The member lines log messages and stats specific to the flexgroup constituent on a node

FlexGroup "master" log example:

• fg_test1 is a FlexGroup
• One constituent resides on node 1, while the other resides on node 2
• This is the log from node 1
• There are two Start lines, one for the entire backup, and the other for a local member constituent
• This log excerpt contains the first Start line
• The NDMP Session, 55050, is logged in the master log messages, and will not appear in the "member" log

dmp Tue Sep 22 08:08:05 EDT 2020 /vserver1/fg_test1/ (34cabf55-a5dd-469e-995f-ac9f225444cb:master)(0) Start (Level 0, NDMP:55050)
dmp Tue Sep 22 08:08:05 EDT 2020 /vserver1/fg_test1/ (34cabf55-a5dd-469e-995f-ac9f225444cb:master)(0) Options (b=0, u, TCP recv buffer size = 33580, TCP send buffer size = 33580)
dmp Tue Sep 22 08:08:05 EDT 2020 /vserver1/fg_test1/ (34cabf55-a5dd-469e-995f-ac9f225444cb:master)(0) Filesystem (/vol/fg_test1__0001)
dmp Tue Sep 22 08:08:05 EDT 2020 /vserver1/fg_test1/ (34cabf55-a5dd-469e-995f-ac9f225444cb:master)(0) Vol-Info (RW, comp=off, dedupe=off, clone=no)
dmp Tue Sep 22 08:08:05 EDT 2020 /vserver1/fg_test1/ (34cabf55-a5dd-469e-995f-ac9f225444cb:master)(0) Granularity (volume)
dmp Tue Sep 22 08:08:05 EDT 2020 /vserver1/fg_test1/ (34cabf55-a5dd-469e-995f-ac9f225444cb:master)(0) Snapshot (snapshot_for_backup.1, Tue Sep 22 08:08:00 EDT 2020)
dmp Tue Sep 22 08:08:05 EDT 2020 /vserver1/fg_test1/ (34cabf55-a5dd-469e-995f-ac9f225444cb:master)(0) Tape_open (ndmp)

• This is the second Start line, for the local member constituent
• These are member messages
• The filesystem contains the constituent name fg_test1__0001, rather than the FlexGroup name, fg_test1

dmp Tue Sep 22 08:08:08 EDT 2020 /vserver1/fg_test1/ (34cabf55-a5dd-469e-995f-ac9f225444cb:member:0001)(1) Start (Level 0)
dmp Tue Sep 22 08:08:08 EDT 2020 /vserver1/fg_test1/ (34cabf55-a5dd-469e-995f-ac9f225444cb:member:0001)(1) Options (b=63, u)
dmp Tue Sep 22 08:08:08 EDT 2020 /vserver1/fg_test1/ (34cabf55-a5dd-469e-995f-ac9f225444cb:member:0001)(1) Filesystem (/vol/fg_test1__0001/.snapshot/snapshot_for_backup.1)

FlexGroup constituent (member) log example:

• fg_test1 is a FlexGroup
• One constituent resides on node 1, while the other resides on node 2
• This is the log from node 2
• As this is a constituent, dump logs the UUID and a "member" number (0002.)
• Not all dump phases are reported here -- The "missing" dump phases are in the "master" backup log on node 1
• There is no NDMP session recorded.  
• The filesystem contains the constituent name fg_test1__0002, rather than the FlexGroup name, fg_test1

dmp Tue Sep 22 08:08:08 EDT 2020 /vserver1/fg_test1/ (34cabf55-a5dd-469e-995f-ac9f225444cb:member:0002)(0) Start (Level 0)
dmp Tue Sep 22 08:08:08 EDT 2020 /vserver1/fg_test1/ (34cabf55-a5dd-469e-995f-ac9f225444cb:member:0002)(0) Options (b=63, u)
dmp Tue Sep 22 08:08:08 EDT 2020 /vserver1/fg_test1/ (34cabf55-a5dd-469e-995f-ac9f225444cb:member:0002)(0) Filesystem (/vol/fg_test1__0002/.snapshot/snapshot_for_backup.1)​​​

Additional Information

Locating NDMP and backup logs for NDMP FlexGroup backup or restore