CARP/HA with keepalived in the network!

PointPubMedia

hey guys....

Having a strange issue since a while and can't figure out why/where!

Sometime, out of no where, CARP failover to backup and back to master in the same minute but not all the vhid at the same time...

When it happen, it screw up the network traffic for this short period... but after thinking a little bit more, I remember that in a particular VLAN, we are having 2 VMs that failover an IP using KEEPALIVED linux package using VRRP!

Is it possible that our VRRP config in both VM, out of no where, can screw up pfSense CARP ?

In keepalived I never never have a log or something when it happen to pfSense...

jimp

CARP and VRRP are very similar. They can interfere with each other but usually that interference only happens if your VRRP VRIDs and CARP VHIDs overlap. The first thing to check is to see if you are using the same IDs there. If so, move to different IDs for one or the other.

It's also possible that the presence of the traffic for both is triggering your L2/Switch to rate limit or block multicast (might be called "storm control")

PointPubMedia

thanks @jimp

Here's a snippet from our keepalived config...

vrrp_instance VI_1 {
    state MASTER
    interface ens18
    virtual_router_id 101
    priority 101
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass xxxxxxxxxxxx
    }
    virtual_ipaddress {
        xxxxxxxxxxxx
    }
}

vrrp_instance VI_2 {
    state MASTER
    interface ens18
    virtual_router_id 102
    priority 101
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass xxxxxxxxxxxx
    }
    virtual_ipaddress {
        xxxxxxxxxxxx
    }
}

and here's our Virtual IP in pfSense (master)

and on the other pfSense, our skew is 100 with a base 1

jimp

At least by ID, I would think that is safe. So you might take a closer look at your switch/L2.

PointPubMedia

We are having L3 switches and I can't find anything about that... I'm thinking more and more that our pfSense appliance is having a hard time with the traffic!