[LARTC] Two Gateways and NAT??

[LARTC] Two Gateways and NAT??

[Lars Landmark]

Hi;

I have two dsl lines, which the low bandwidth connection(ISP2) is only
used for failover.  My setup is showed below;

             \             ISP1
              \            /
               \      ____/NAT
My internal net |-----|___|
                /         \NAT
               /           \
              /            ISP2


However, my interfaces which these lines are connected are both using NAT.
My question is; will TCP connections that NAT.ed over interface ISP1
break if a failover happens and rerouted over ISP2??

Lars

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Re: [LARTC] Two Gateways and NAT??

[Damion de Soto]

Hi,
Lars Landmark wrote:
> I have two dsl lines, which the low bandwidth connection(ISP2) is only
> used for failover.
-----8<-----
> 
> However, my interfaces which these lines are connected are both using NAT.
> My question is; will TCP connections that NAT.ed over interface ISP1
> break if a failover happens and rerouted over ISP2??
Yes, all your tcp connections will need to be re-established.
the only way around this is to have both main and failover ISP/s do
some multi-path routing trickery - which is probabaly very unlikely.

regards,

-- 
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