[lvs-users] load balancer IP limit?

[Steve Haneman <stevehaneman@xxxxxxxxx>]

Hello,

I'm using ipvsadm to load balance 2 security web servers, so I'm using 3 boxes.

1 load balancer box
---------------------

LSB_VERSION="1.3"
CentOS release 4.0 (Final)
kernel: 2.6.9-42.0.2.ELsmp
ipvsadm v1.24 2003/06/07 (compiled with popt and IPVS v1.2.0)

The lb box has
    - 200 VIP address in the 172.16.16.x range
    - 1 IP in the 192.168.253.x range used as the gateway IP for the web servers


2 security web servers
----------------------

CentOS release 5.2 (Final)
Version 3.5.0 (Build 52714)
kernel: 2.6.18-92.1.10.el5

The web servers have 100 IPs each in the 192.168.253.x and 192.168.252.x ranges.


Here is how I set up my load balancer:

    system("/sbin/ipvsadm -C");
    for (my $x=11; $x <= 111; $x++)
    {
            system("/sbin/ipvsadm -A -t 172.16.16.$x:443 -p 1500 -s rr");
            system("/sbin/ipvsadm -a -t 172.16.16.$x:443 -r 192.168.253.$x:443 
-m -w 1");
            system("/sbin/ipvsadm -a -t 172.16.16.$x:443 -r 192.168.252.$x:443 
-m -w 1");
    }

I'm finding that 4% of the time the sessions are not sticky.  A user/password 
web POST goes to one server and a followup POST ends up at the other server.

--Steve