AW: Now ok for 1.04. But some question about sync and serial .....

Hi Giulius,

> I would like to build a 2 node without shared storage disks 
> cluster for HA my ftp server.
> All data file must be replicated between 1st and 2nd node.

You can use drbd as a "poor mans" substitute for shared storage. have a look
at http://www.linbit.com/en/ for more information and download of drbd. in
short, it provides block device replication over the network.

> Reading the AG, i found that failsafe need a serial line between 2 or 
> more NODE in a CLUSTER.
> Is it true? If yes why? The only pourpose of a serial line is to shut 
> down and doing remote management system?

No it's not true. You do, however, need SOME way to shut down / reset a node,
esp. if you're using shared storage (or drbd) to avoid data corruption.

The usual way of implementing these cluster reset services in linux is by
using the stonith library from the linux heartbeat project
(http://www.linux-ha.org/download/), which supports quite a few different
devices/methods.

For testing the software and experimenting with different setups, stonith can
use ssh to reset the other node - this is obviously not an option for a
production evironment, where something like the WPS power switches or APC
masterswitch or ... should be used.

Bye, Martin