[nsp] High-availabity GigE connection to two switches

[Pete Templin]

Arnold Nipper wrote:
> On 01.06.2004 22:22 Tony Li wrote:
> 
>>My preference would be to take the obvious approach and make them two
>>separate subnets.  But then I'm weird...
> 
> But that might lead to problems with ARP. I've a /23 here and some
> connect to the network with one router and two interfaces, each a /24.
> Let's say 10.0.0.1/24 on first and 10.0.1.1/24 on second. Now if
> 10.0.0.2/23 arps for 10.0.1.1/24 the reply will leave on a differenr
> interface the request came in. And e.g. Cisco routers don't like it :-(

Treat the two Ethernet segments where the servers connect to the 
switches as infrastructure segments, and put individual subnets (for the 
"end" resources) on virtual interfaces within the server (MS Loopback 
Adapter comes to mind).  Have the server announce the virtual interface 
to the rest of the infrastructure (RIP, OSPF, etc.).  This way, you 
abstract the connectivity from the service, particularly the address 
referenced by DNS.  (Also great for load balancing, etc.)

Just my $0.01,

pt