Jordan Gordeev wrote:
The only load balancing that CARP supports, to my knowledge, is ARP level load balancing. From carp(4):
The ARP load balancing has some limitations.  First, ARP balancing only
    works on the local network segment.  It cannot balance traffic that
    crosses a router, because the router itself will always be balanced to
    the same virtual host.

Forgive me for stepping in, but I had read the above statement over and over trying to figure what it meant; perhaps it's not so clear...

If I understood it correctly it's not saying you should not use CARP on routers. Instead it's meaning that load-balancing won't cross a third router which is on cascade of the two CARP routers.
An image might help to clarify:

+------+ +------+ +------+ .... +------+
|host I| |host J| |host K| .... |host Z|
+------+ +------+ +------+ .... +------+
   |        |        |              |
   \--------+--------+-------------+---------\
                                             |
+------+ +------+ +------+ .... +------+ +--------+
|host A| |host B| |host C| .... |host H| |Router 3|
+------+ +------+ +------+ .... +------+ +--------+
   |        |        |             |         |
   \--------+-----+--+-------+-----+---------/
                  |          |
             +--------+ +--------+
             |Router 1| |Router 2|
             +--------+ +--------+


Suppose you are arp-balancing with CARP on Router 1 & 2, hosts A-H will get balanced, but hosts I-Z will all go to the same router (wether Router 1 or Router 2). This is because all their incoming packets will bear Router 3's MAC address.


Is this interpretation correct?


 bye & Thanks
        av.
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