Replication and snapshots

[abatie]

I'm looking at off the shelf solutions for a replicated fileserver (with multi-terabyte volumes, recovering by copying backups is just not workable), and it looks like ReadNAS is *almost* there; I'm posting this as a wishlist for features that should be very incremental to the existing product line:

Replication:

* I don't want a third party site involved with my fileserver management. I don't need it, it's a security risk, I don't want to pay for it and it adds to the requirements for a working setup. I just want to tell one readynas to replicate to the other one. There should be some sort of authentication of course, but I would set the replication to happen on a private network (be it local, vlan or vpn; the current products with replication capability have more than one network interface) so could live without encryption, though that would be a nice plus.

* In case of total server failure (i.e. chassis hardware failure), I want to be able to switch to the replica, come back up, order a new server and set it up as the new replica. I don't need automatic failover, which is much more complicated.

Snapshots:

* Ideally, there would be 4-24 "hourly" (4=one every 6 hours, to 24=one every hour) snapshots, 7 dailys, 4 weeklies and a monthly or two. One might not have enough disk space for that many, but that's the ideal; 1 single snapshot isn't enough though

I have been using zfs on opensolaris without replication (backing up to a readynas) and just had a server failure. I'm now running off the readynas and building a new server. If the readynas solution was a little more complete, I would just get a pair of ultra 4's, but it looks like I'll have to roll my own with nexenta at the moment...