routing table madness

[David A. Bandel]

On Mon, Nov 5, 2012 at 9:08 PM, Lonni J Friedman <netllama at gmail.com> wrote:
[snip snip snip]
>>
>> I could use a little more detail, but this is easily fixable.  Tell me
>> what needs to route where and I'll send you a list of commands.
>
> Thanks!  The *only* thing that should ever be routed over em1 is
> traffic for 10.0.0.101.  Everything else should go out over em3.  Let
> me know if you need any other specifics, and I'll provide them.

Then make the netmask for em1 be 255.255.255.0 (/24) or even smaller
(you could make this interface a /29 -- 255.255.255.248, but not a /30
because .100 is the network address for that network, so the hosts
would have to be .101 and .102 w/ .103 the broadcast).

It is also possible to not use a bridge but to create a policy routing
table for those things destined for the one host on em4
in /etc/iproute/rt_table you would need a named entry, say foo with a
number (see example), then:
ip ru add to 10.31.96.100 table foo

but your best bet is still a bridge over em3 and em4, especially if
either one interface comes up and goes down or an IP will be connected
to one or another (but not active on both simultaneously) interface.

HTH,

David A. Bandel
-- 
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