Help with keepalived for linode failover

Hello, I made a post a bit ago about getting keepalived working. It's now running, but from the looks of it my linodes (although they can ping eachother and iptables is completely permissive between both of them) are not registering with eachother when keepalived starts up.

Doing a "ip addr sh eth0" shows me that both nodes are grabbing the shared IP, and aren't communicating with eachother.

Reading about keepalived and VRRP have proved futile, so I'm hoping someone on here who has experience with them (or just multicasting in general) can help me out. I don't know how to debug the connection between the two machines, even after reading up on VRRP and multicasting.

I CAN ping and access the shared IP (even though both machines claim it), and it seems to intermittently switch between the two…which I guess would provide some sort of failover, but I want this working right. Any ideas? Here's my config, if it helps.

global_defs {
    notification_email {
         info@dotdotdot.com
    }

    notification_email_from alerts@dotdotdot.com
    smtp_server localhost
    smtp_connect_timeout 30
    router_id  
}

vrrp_script chk_haproxy {
    script "killall -0 haproxy"
    interval 2
    weight 2
}

vrrp_instance VI_1 {
    state MASTER
    interface eth0
    virtual_router_id 51
    priority 101 

    advert_int 1
    garp_master_delay 2

    smtp_alert

    authentication {
        auth_type PASS
        auth_pass pwdpwdpwd
    }

    virtual_ipaddress {
        69.164.201.xxx
    }
    track_script {
        chk_haproxy
    }
}