It is different in that the snapshots represent read only copies of the files in the filesystem. When you use NFS to mount the snapshot and copy the files to tape, Legato will still look at the time stamps on the files and backup the files that have changed since the time stamp in the Legato client file index. This means that Legato will backup files that have changed since the last backup if you specify an incremental backup. However, that is different than the block level changes that are always ongoing in the WAFL filesystem, and it is that characteristic that enable snapshots to work. All of the stuff related to WAFL (internal filesystem stuff) is, and has to be transparent to the backup software and even the operating system. Based on all of that stuff it looks to me like Legato can not do what you are looking for.
"E.J. Jantz" ej_jantz@bswintl.com 04/25/01 08:55AM >>>
just a question: If the 'snapshots are "copy on writes' doesn't that mean that a backup of .snapshot is equal to and functions as a full backup? If not, can Legato using a NFS mount on a unix server capture just the info the .snapshot uses? If so, how?
thanks...
EJ Jantz, IST Dept. BSW International One West Third, Ste 100 Tulsa, OK 74103-3505 918 582-8771 ej_jantz@bswintl.com 918 295-4166 918 587-3594 fax
"Clawson, Simon" simon_clawson@mentorg.com 4/25/01 4:32:08 AM
Is it possible to backup just the .snapshot and then perform a restore from this data?
I am looking for ways to speed up the backups and this seems to be a possible option. It was suggested to me by a colleague as a method of backing up Clearcase VOBS, but would it be viable for the whole filer. Of course I would need to run a full backup at tleast once a month, but this would help me speed up most of my weekly runs.
Any ideas/suggestions/views?
Simon
Simon Clawson HDS Team Systems Administrator Mentor Graphics Uk Rivergate London Road Newbury Berkshire RG14 2QB <<Clawson, Simon.vcf>>
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Rick Hulsey