[Nottingham] Distributed filesystems

[Andy Davidson]

On Monday, March 8, 2004, at 11:58  am, Graeme Fowler wrote:
> Other than those who I've already chuntered about this to, does anyone 
> have
> much experience of the use of Linux distributed filesystems? I'd 
> appreciate
> hearing about anything to do with:
> software RAID using the nbd or enbd kernel modules

Hi, dude --

We wanted to use drdb (www.drdb.org) to setup a RAID-1-like sharing of 
a distributed volume spanning two identically configured production 
servers which were failovers of each other.

Ultimately /usr/local (ha, ironically titled) which stored a bunch of 
CGIs - changes on one server were to be reflected on another server.

When they had a crossover cable, it was quite quick - not dis-similar 
results to what's claimed you can achieve on the drdb.org site.  When 
they were going across the normal switch (which was what we wanted them 
to use, the crossover cable pinched the interface for the backup 
network) we got shocking results, something like 10kB/sec.

YMMV, I'd love to see someone improve on that. :-)

Installing drdb is easy, it's a patch for linux 2.4.blah which you 
build as a module.  I think it's supposed to be used to distribute a 
database in an Oracle RAC stylee fashion.

Please keep us up to date when you find something out, as we're back to 
rsyncing when we make changes to the scripts.

Andy