So again lets ask what is routing these networks? And how exactly do you have this host connected to both? What is its routing table.. Is it windows machine - post up
route print
If linux
netstat -r
"If I have a host that needs to be in two networks to separate the traffic that needs to be separate"
Why??? does a host need to be in 2 networks at the same time… If he is in 99, and needs to talk to something in the 66, why can you not route this traffic??
Yes you can have machine connected to more than 1 network at a time, but you wouldn't use both of these networks to route to a default.. So for example you could have the attached pic. Where machines have an interface in 192.168.0/24 this would be their default gateway.
They then could have another interface in 192.168.1/24 and they could use this interface to talk to each other - lets say for backup or something.. But you would need to make sure you use the 192.168.1 IP address of the other machine, or a fqdn that resolves to that 192.168.1 IP. And 192.168.1 interface would not have any gateways set on it, etc etc..
multihomed.png
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