Bhakti,  There are a couple different option here that could be done to correct the fact that the owner of most of your migrated files are owned by admin or another high level user. While both will be time consuming, they both offer some pluses in different areas.  You could configure directory quotas on each directory for each user: The nice thing about this configuration is that directory quotas allow you to set the visible size of the share to that of the hard quota. So if you have a 800TB cluster and each user directory Eg. /ifs/data/home/user1 has a hard quota of 1TB, the users share would report a 1TB size. Down side to this is configuring each quota could be time consuming.  You could also work to "chown" the files in each user directory recursively based on the correct owner of the files. isi720x-1# chown -R \\  Once the directories have the correct owner you can set up a single default user quota on the "home drive" directory, and each individual quota will be created automatically with the same configuration as the default. This may prove to save some time as only one quota creation is needed, however the size of the share would be reported as the full cluster size following the above example 800TB.  I would recommend taking a look at the respective administration guide for more information around quota types and configuration. 7.2.0.x CLI guide (Page 691) [URL] 7.2.0.x Webui guide (page 339) [URL]
We migrated the home folders from Celerra to Isilon over a year ago. In the process if migrations we as admins had to take ownership of the files to migrate. We recently enables smartquotas on home folders and see very off results. If we see the report on smart quotas by user, it doesn't match the top 10 directories that I see otherwise. Our thought is this is due to file ownership under individual folders. As administrators we own many files of various users and can get to accurate information thus failing in our effort to apply quotas. Is there an easy way to apply ownerships to the respective users ? 
Smartquotas on home drive 