> Hello,
>
>On Thu, 22 May 2003, Aihua Liu wrote:
>
>> I wonder if the Director can rewrites both the source IP address and
>> destination IP address for all packets. For example, Director replaces
>> the destination IP address with real servers' IP address and replaces
>> the source IP address with Director private IP address for incoming
>> packets. Then real servers don't have to set the Director as default
>> gateway. LVS can do it? Thank you
>
> That will need allocating unique TCP/UDP port in the
>director for each conn to the real servers.
Can you tell me why? Currently LVS-NAT mode don't need allocate unique
TCP/UDP port in the director for each conn.
>
> It is not a big pain to use the LVS box as default router
>for the real servers in LVS-DR mode. We already do it for LVS-NAT.
>You can always patch your routing in the LVS box in a safe manner
>with forward_shared flag:
>
>http://www.ssi.bg/~ja/#lvsgw
>
> The LVS HOWTO contains examples how to do it exactly.
>
> Anyone who worry about bandwidth problems can give it a try.
>In IPVS for 2.4 the difference in forwarding NAT and DR is small.
>So, choosing NAT or DR depends only on the ability to
>route properly the packets and on the real server setups: for
>some admins it is preferred the servers to listen on VIPs, etc. For
>others it is difficult to solve the ARP problem with DR (eg. patches not
>present in real server's kernels or difficult to do it in other OSes).
>So, there are different but _possible_ alternatives.
>
>Regards
>
>--
>Julian Anastasov <ja@xxxxxx>
>
I want to implement this for multi-directors loadbalancing.
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