Director and Real servers on different networks

[Joseph Mack NA3T]

On Wed, 11 Oct 2006, Andre Nathan wrote:

> Hello
>
> I have an LVS-DR setup which is working correctly like this:
>
>
>       +--------------+
>       | LVS director |
>       +--------------+
>         /    |    \
>        /     |     \
>       /      |      \
>    +---+   +---+
>    |   |   |   |    ...
>    +---+   +---+
>        Real servers
>
>
> The director and the real servers are all on the same network (say,
> a.b.c.0/24) and share an IP address (say, a.b.c.d) for the load-balanced
> service.

I'll assume this means that all machines have the VIP=a.b.c.d

> Now, we're migrating to a new range of IPs (say, x.y.z.0/24). I've tried
> adding a new real server (which has its real IP on the new range, say,
> x.y.z.w) to the existing configuration (that is, added a.b.c.d as an
> address to a dummy interface).

I assume the director can route to the new network and that 
you've added the VIP to the new realserver on dummy0

> The configuration seems to be working correctly (i.e., the connections
> are redirected to this new server). However, ipvsadm always reports the
> number of active connections as 0 for that server, and thus all new
> connections are being redirected to it, and none to the pre-existing
> servers (I'm using the wlc algorithm).
>
> Is this a supported configuration?

yes

> Is there some assumption made by ipvsadm on the servers 
> being all on the same network,

no

> or that dummy interface addresses and real addresses must 
> be on the same network?

no. the real addresses are usually private eg 192.168.1.0/24 
while the VIP is a public IP.

This should work. I assume you've done something silly. 
Quite what silly is may not be obvious though.

Joe



-- 
Joseph Mack NA3T EME(B,D), FM05lw North Carolina
jmack (at) wm7d (dot) net - azimuthal equidistant map
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