mrcgran writes "I have a group of different Linux boxes (two desktops at home and work, a laptop and a PDA) and I would like to replicate a file system among them with no hassle at all, so that my working set is the same no matter where I am. The perfect solution would be one in which, for each box, I run a background replicator process and point it to some local block device. For each local write access in this device, the replicator asynchronously commands the peers in the group to mirror the action on their own local devices over ssh, stunnel or other secure protocol. Replicators can be added and removed from this group at any time. I might even have two replicators running on the same machine pointing to two different local block devices (RAID1-like). There is no need to replicate at block level, indeed replicating at file level would simplify me resizing the block devices in the future.
I wasn't able to find an open-source solution for the problem above. Pratima, for instance, is asynchronous but it seems to be client-server and difficult to setup in a dynamic group, similarly to DRBD. Lustre is not truly P2P but depends on a master node managing meta operations. Other fail-tolerant file systems are even more difficult to set up. What replication service do you use? Does anyone know of any which might be as useful and hassle-free as the perfect solution above?"