[Lustre-discuss] MDT estimated time for backup

[Ms. Megan Larko]

Hello List,

I still have not yet backed up my MDT onto a larger  LV.   (My users
like availability times in the monthly range; fortunately Lustre is
good enough to provide that to them.)   To execute the getfattr and
tar used to take me 3 to 8 hours.    My last attempt had tar -cf
running for over two days which was not acceptable to my users.  I
would really like to get this work done and to provide my users with a
realistic estimate of the time Lustre disks will be unavailable to
them.   The MDT is:
/dev/sdf               58G  Total Size       3.4G Used      51G Avail
 7% /srv/lustre/mds/crew8-MDT0000.

The current inode usage is (from df -ih):
/dev/sdf                 17M     14M    2.5M   86% /srv/lustre/mds/crew8-MDT0000

What would be a reasonable time estimate to back this up?   Is
getfattr and tar still preferred over rsync -aS  or the getfattr and
dump method?

Thank you,
megan