load balancing at fastmail.fm

[David Lang]

On Mon, 12 Feb 2007, urgrue wrote:

>> If it's using block level replication, how does it offer instant recovery 
>> on filesystem corruption? Does it track every block written to disk, and 
>> can thus roll back to effectively what was on disk at a particular instant 
>> in time, so you then just remount the filesystem and the replay of the 
>> journal should restore to a good state?
> Yes. I may be wrong but to my understanding at least NetApp has this 
> capability.

No, NetApp takes snapshots of the filesystems on a schedule (hourly, daily, 
weekly, etc), and you can read files off of those snapshots. you cannot getany 
more granular then that.

David Lang