Mounting specific filesets

By using the Lustre fileset feature, you can mount only a subset of the cache namespace, which is called a fileset. To mount a fileset of the cache on the client, specify the subdirectory path after the cache name. A fileset mount (also called a subdirectory mount) limits the cache namespace visibility on a specific client.

Example – Mount a Lustre fileset

1. Assume that you have a cache with the following directories:

   team1/dataset1/
   team2/dataset2/

2. You mount only the team1/dataset1 fileset, making only this part of the cache locally visible on the client. Use these commands and replace the following items:

   • Replace cache_dns_name with the actual cache's DNS name.

   • Replace mountname with the cache's mount name. This mount name is returned in the CreateFileCache API operation response. It's also returned in the response of the describe-file-caches AWS CLI command, and the DescribeFileCaches API operation.

   mount -t lustre -o relatime,flock cache_dns_name@tcp:/mountname/team1/dataset1 /mnt

When using the Lustre fileset feature, keep the following in mind:

• Before a cache directory can be mounted on a client, you must list the directory by running the ls command on a parent directory in the cache.

• There are no constraints preventing a client from remounting the cache using a different fileset, or no fileset at all.

• When using a fileset, some Lustre administrative commands requiring access to the .lustre/ directory might not work, such as the lfs fid2path command.

• If you plan to mount several subdirectories from the same cache on the same host, keep in mind that this consumes more resources than a single mount point, and it could be more efficient to mount the cache root directory only once instead.

For more information about the Lustre fileset feature, see the Lustre Operations Manual on the Lustre documentation website.