An anonymous reader writes: What options are there for folks who want to have synchronized filesystems on Internet-connected Linux machines, like at two associated branch offices sharing common data, or a small office with an off-site machine maintained for disaster recover purposes? The files should appear to be local at both locations (caching and file-locking), and changes need to propagate efficiently between the two systems. If the Internet connection becomes temporarily unavailable, the data kept as available as possible on each end in the interim.
We're not talking about rsync-replicated snapshots, although those are useful too, but rather live, fast access to a shared filesystem, with the geographical separation transparent to the end users. If the filesystem is large, it can initially be "seeded" from an image on tape(s)/disk(s)/dvd(s). Both sides should be able to access the common data over local Samba shares, too, if they want.
Production quality reliable solutions that work over DSL-type connections are what we're looking for...
