I'm would like to have a filesystem for network-mounted home directories that can scale easily (per user) at a low cost. EFS seems well-suited to this (especially with Infrequent Access enabled). However, I cannot see a way to set quotas on a per-user basis.
I know typically quotas are set in kernel-space for physical volumes, but I don't think it's possible for NFS volumes (the quotas have to be set on the NFS server, which is the EFS service).
Are there any other things I might explore to restrict how much space users can store in their EFS-mounted homedirs? Or should I be looking to another service?
In general, NFSv4.x protocol supports quotas. However, according to EFS documentation, quotas are not supported in Amazon's implementation. If you need to run it in amazon cloud, then one option will be to create an EBS volume, attache it to a small instance and export it with nfs. If you format volumes with zfs or btrfs, then you can add new volumes if required, as single EBS volume is limited with 16TB. You will miss the whole amazon management interface, of course.