LVS
lvs-users
Google
 
Web LinuxVirtualServer.org

granularity/balancing issue with a small number of client IPs

To: "LinuxVirtualServer.org users mailing list." <lvs-users@xxxxxxxxxxxxxxxxxxxxxx>
Subject: granularity/balancing issue with a small number of client IPs
From: Stefan Schmidt <zaphodb--lvs-users@xxxxxxxxxxx>
Date: Wed, 15 Nov 2006 17:31:17 +0100
Hi there,
i have a problem loadbalancing DNS udp/53 via LVS DR.
Whenever i have a small number of clients, in the example below it is DNS
realtime blackhole lists used by 10 mailservers.
Redundancy is working fine but granularity seems to be an issue and there is
times when i end up with something like this:
#ipvsadm --list --rate --numeric
UDP  1.2.3.4:53                          0     1889        0   173253        0
  -> 10.1.53.15:53                       0        0        0       18        0
  -> 10.1.53.9:53                        0     1889        0   173235        0

configuration looks like this:
virtual_server 1.2.3.4 53 {
        delay_loop 10
        lb_algo wrr
        lb_kind DR
        protocol UDP
        ! persistence_timeout 1
        ! persistence_granularity 255.255.255.255
        real_server 10.1.53.9 53 {
        ...

Same picture if i uncomment the persistence statements.

I noticed there apparently are some slewing algorythms doing things like a slow 
start whenever i add a realserver but i never stumbled over any documentation,
can you give me a hint on where to look for this?
I would want it to be a little less 'soft'.

best regards,
                Stefan
-- 
panic("Oh boy, that early out of memory?");
2.2.16 /usr/src/linux/arch/mips/mm/init.c 

<Prev in Thread] Current Thread [Next in Thread>