[rhelv6-list] Red Hat 6.4, keepalived and ipv6

[Martinsson Patrik]

Hello, 

This is not a specific Red Hat 6 question, but there seems to be a lot of people with general knowledge here so I'm going to take my chances. 
Already tried keepalived-mailinglist but no answer. 


I'm really trying to understand how keepalived handles ipv6 VIP's and what's the general idea and best practise is, however I seem to miss something. 
I don't understand why you wouldn't want to have keepalived to set the preferred_lft to zero when bringing up the VIP's, or actually what I don't understand is how to make various checks work with the source-address beeing the VIP and not the "iron-address". 

So, here's the simple configuration, 

# keepalived.conf, 
global_defs {
   notification_email_from foo at bar.com
   smtp_server bar.com
   smtp_connect_timeout 30
   lvs_id ER-TST-LD-MASTER
}

vrrp_instance VI_1 {
        state MASTER
        interface eth0
        lvs_sync_daemon_interface eth0
        virtual_router_id 56
        priority 150
        advert_int 1
        smtp_alert
        authentication {
                auth_type PASS
                auth_pass example
        }
        virtual_ipaddress {
           XXXX:XXX:XXX:XXXX::46 
        }
}

virtual_server XXXX:XXX:XXX:XXXX::46  0 {
    delay_loop 10
    lb_algo rr
    lb_kind DR
    persistence_timeout 900
    protocol TCP
    real_server XXXX:XXX:XXX:XXXX::17 0 {
        weight 1
        inhibit_on_failure
        MISC_CHECK {
          misc_path "/etc/keepalived/check_tcp -H XXXX:XXX:XXX:XXXX::17 -p 21"
          misc_timeout 30
        }
    }
}
# end keepalived.conf 


So, this would mean that when keepalived performs the check to see if the realserver (XX:17 on port 21) is alive, the source-address of that packet is the VIP (XX:46), which of course also is up on the realserver, which in turns would mean that the packet never returns to keepalived. And thus making keepalived to mark the realserver as down (since it doesnt get any reply). 

So, what I'm I missing here, how is this suppose to work ? 

I've been trying to read the following discussions, they seem to have the same problem, 
http://www.ietf.org/mail-archive/web/v6ops/current/msg15266.html
http://marc.info/?l=keepalived-devel&m=130200733315039 (there's a patch that would make sense to me, but never got accepted if I'm not mistaken) 


Patrik Martinsson
ITi

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