clients
|
internet
|
gateway (G)
|
_______________________________________|________________________
| | | | | | | | | |
__|_|__ __|_|__ __|_|__ __|_|__ | | | | | |
| | | | | | | | other clients
| A | | B | | C | | D |
|_____| |_____| |_____| |_____|
I'd like to setup an LVS for the above where A, B, C, and D are all on the
same subnet and have two NICs. The only port I need setup is ssh. I was
wondering if the following is feasible:
- A, B, C, D are realservers.
- Any client can directly access A, B, C, D.
- A is the director.
- When any client connects to the second interface on A, they could be
sent to B, C, or D depending on load and all LVS traffic is sent to the
second interfaces on B, C, and D.
- B is a director failover.
What has tripped me up is not understanding the same-subnet issue. As the
very first step toward implementing this, I initially raised the second
interface on A (different IP, same subnet) and was then able to connect to
it via either interface. When I then lowered the second interface, I was
still able to connect to A on either interface. (the hostnames given to
eth0 and eth1 were both responsive even though the cable was physically
unplugged from eth1.)
I believe LVS-Tun is what I should use since it fits the above contraints
in the HOWTO. (no port remapping, *realserver network is on internet*,
realserver default gw (g) is own router) A, B, C, and D all happen to be
running Linux.
Is it required that the second interfaces on A, B, C, and D be on a
different (local) subnet? Otherwise, I don't see how LVS traffic can be
managed since A, B, C, and D already have a default gateway set to G.
There are clearly some larger network issues that I don't understand so I'd
appreciate any guidance on what direction to look into.
Thanks for your time,
Ryan
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