It looks like XFS, doesn't work very well with opnewrt, I had problems with an USB harddrive and an USB flashdrive. So which filesystem should I choose especially for movies and minidlna?
I found:
http://wiki.openwrt.org/doc/howto/usb.storage
We recommend the file systems ext2, ext3, or ext4 (all supported by kmod-fs-ext4)
and http://wiki.openwrt.org/doc/techref/filesystems
So is ext4 recommended or do I better use ext3 or ext2 with an USB flashdrive?