Way to make distant servers to appear to have the same data ?

[Gordon Charrick]

David Timms wrote:
> What is the most effective, most robust way to allow servers that are 
> quite distant, and on slow networks "appear" to have the same content ?
> 
> In my example, the content is read/write at 4 sites. Hopefully the 
> system should make caching possible for files that were originally at 
> another site. If a file were not already cached, then it would get 
> loaded across the slow network.
> 
> redhat global file system appears to be designed to do this:
> http://linux.sys-con.com/read/166309_2.htm
> but then talks about storage area network or LAN connections rather than 
>  slow wan links.
> 
> http://www.drbd.org/ raid across machines?
> 
> I did see a few other projects designed to solve this sort of problem, 
> but I am having trouble finding them now {search hints ?}
> 
> http://www.coda.cs.cmu.edu/ljpaper/lj.html
> 
> Has anybody used / appraised coda ?
> 
> David Timms.
> 

OpenAFS (http://www.openafs.org) is the perfect piece of software for 
this. We used the commercial version of this way back in the 90's when I 
worked for NIH. It's designed for WAN's and uses a local cache for 
content. It is somewhat complicated so it's not some install it and run 
it application.

Gordon