Hi,
On Tue, 2004-11-16 at 14:17, Richard_D_Levine@raytheon.com wrote:
> Hi Chris and Karim,
>
> I haven't been following this thread, so excuse me if I suggest something
> that has already been tossed out.
>
> Solaris allows multiple IP addresses to be assigned to a single NIC. I
> just looked at the man page for Linux ifconfig but didn't see quickly how
> to do this. If Linux doesn't allow this, the same thing can be
> accomplished using multiple NICs per server.
>
> We reserve a special IP for the DB server. This IP can be assigned to the
> NIC of the machine currently hosting the database. If you want apps to
> connect to a different server, remove the IP from one machine and reassign
> it to the other. This special DB IP is assigned on top of the regular IP
> for the machine.
>
> Newly connecting apps are never the wiser, but existing connections must be
> terminated.
Yes, linux can do it as well. But either case beware the arp cache :-)
There is sqlrelay which could do the switching as well without
forcing the apps to reconnect.
Regards
Tino