Thank you Andreas, the lots of small files scenario what the main reason I was looking into the loop device. As for the ext3, it was a quick example I had found on the net. I appreciate your advice on going to ext2 instead. I don't want to put my large lustre system into trouble.
One thing I might be looking for in the future is something that does the same thing but is encrypted and user level mountable. I might have future users that have sensible data and simple UNIX ownership isn't enough. Richard Andreas Dilger wrote: > On 2009-12-05, at 16:13, Richard Lefebvre wrote: >> Would it be safe to create a file on a lustre file system and use it as >> a loop device for mounting? >> >> Sort of doing something like this (creates a 100G file): >> >> mount -t lustre msdser...@o2ib0:/lustre /mnt/lustre >> dd if=/dev/zero of=/mnt/lustre/myfsfile bs=1024 count=104857600 >> mkfs.ext3 /mnt/lustre/myfsfile >> mkdir /mnt/myfs >> mount -o loop /mnt/lustre/myfsfile /mnt/myfs > > > You mean like sanity.sh test 54c does? Yes. However, I'm not totally > sure that ext3 on top of a loop device is "safe", regardless of > whether this is Lustre or not. > > Some users do this (with ext2) to have a node-local mechanism for > accessing a lot of small files. It is also possible to use such > loopback files in read-only mode (again with ext2 only) from many > nodes at one time. > > Cheers, Andreas > -- > Andreas Dilger > Sr. Staff Engineer, Lustre Group > Sun Microsystems of Canada, Inc. _______________________________________________ Lustre-discuss mailing list [email protected] http://lists.lustre.org/mailman/listinfo/lustre-discuss
