So I'm playing around with S3 and elasticdrive, and I create a filesystem on it with a block size larger then 4k. mkfs.xfs -b size=8k /mnt/ed5/ed0 -f This completes fine and sets up the proper filesystem. When I try to mount it, however, I get: mount /mnt/ed5/ed0 /mnt/eds35/ -o loop mount: Function not implemented looking at dmesg I get: XFS: Attempted to mount file system with blocksize 8192 bytes XFS: Only page-sized (4096) or less blocksizes currently work. XFS: SB validate failed I had similar issues with reiserFS. Is there a way to get a filesystem with larger then 4k blocks in CentOS 5? Russ