Comment 0 for bug 1815101

Configure netplan for interfaces, for example (a working config with IP addresses obfuscated)

network:
    ethernets:
        eth0:
            addresses: [192.168.0.5/24]
            dhcp4: false
            nameservers:
              search: [blah.com, other.blah.com, hq.blah.com, cust.blah.com, phone.blah.com]
              addresses: [10.22.11.1]
        eth2:
            addresses:
              - 12.13.14.18/29
              - 12.13.14.19/29
            gateway4: 12.13.14.17
            dhcp4: false
            nameservers:
              search: [blah.com, other.blah.com, hq.blah.com, cust.blah.com, phone.blah.com]
              addresses: [10.22.11.1]
        eth3:
            addresses: [10.22.11.6/24]
            dhcp4: false
            nameservers:
              search: [blah.com, other.blah.com, hq.blah.com, cust.blah.com, phone.blah.com]
              addresses: [10.22.11.1]
        eth4:
            addresses: [10.22.14.6/24]
            dhcp4: false
            nameservers:
              search: [blah.com, other.blah.com, hq.blah.com, cust.blah.com, phone.blah.com]
              addresses: [10.22.11.1]
        eth7:
            addresses: [9.5.17.34/29]
            dhcp4: false
            optional: true
            nameservers:
              search: [blah.com, other.blah.com, hq.blah.com, cust.blah.com, phone.blah.com]
              addresses: [10.22.11.1]
    version: 2

Configure keepalived (again, a working config with IP addresses obfuscated)

global_defs # Block id
{
notification_email {
        <email address hidden>
}
        notification_email_from <email address hidden>
        smtp_server 10.22.11.7 # IP
        smtp_connect_timeout 30 # integer, seconds
        router_id system3 # string identifying the machine,
                                     # (doesn't have to be hostname).
        vrrp_mcast_group4 224.0.0.18 # optional, default 224.0.0.18
        vrrp_mcast_group6 ff02::12 # optional, default ff02::12
        enable_traps # enable SNMP traps
}
vrrp_sync_group collection {
        group {
                wan
                lan
                phone
        }
vrrp_instance wan {
        state MASTER
        interface eth2
        virtual_router_id 77
        priority 150
        advert_int 1
        smtp_alert
        authentication {
                auth_type PASS
                auth_pass BlahBlah
        }
        virtual_ipaddress {
        12.13.14.20
        }
}
vrrp_instance lan {
        state MASTER
        interface eth3
        virtual_router_id 78
        priority 150
        advert_int 1
        smtp_alert
        authentication {
                auth_type PASS
                auth_pass MoreBlah
        }
        virtual_ipaddress {
                10.22.11.13/24
        }
}
vrrp_instance phone {
        state MASTER
        interface eth4
        virtual_router_id 79
        priority 150
        advert_int 1
        smtp_alert
        authentication {
                auth_type PASS
                auth_pass MostBlah
        }
        virtual_ipaddress {
                10.22.14.3/24
        }
}

At boot the affected interfaces have:
5: eth4: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether ab:cd:ef:90:c0:e3 brd ff:ff:ff:ff:ff:ff
    inet 10.22.14.6/24 brd 10.22.14.255 scope global eth4
       valid_lft forever preferred_lft forever
    inet 10.22.14.3/24 scope global secondary eth4
       valid_lft forever preferred_lft forever
    inet6 fe80::ae1f:6bff:fe90:c0e3/64 scope link
       valid_lft forever preferred_lft forever
7: eth3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether ab:cd:ef:b0:26:29 brd ff:ff:ff:ff:ff:ff
    inet 10.22.11.6/24 brd 10.22.11.255 scope global eth3
       valid_lft forever preferred_lft forever
    inet 10.22.11.13/24 scope global secondary eth3
       valid_lft forever preferred_lft forever
    inet6 fe80::ae1f:6bff:feb0:2629/64 scope link
       valid_lft forever preferred_lft forever
9: eth2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether ab:cd:ef:b0:26:2b brd ff:ff:ff:ff:ff:ff
    inet 12.13.14.18/29 brd 12.13.14.23 scope global eth2
       valid_lft forever preferred_lft forever
    inet 12.13.14.20/32 scope global eth2
       valid_lft forever preferred_lft forever
    inet 12.33.89.19/29 brd 12.13.14.23 scope global secondary eth2
       valid_lft forever preferred_lft forever
    inet6 fe80::ae1f:6bff:feb0:262b/64 scope link
       valid_lft forever preferred_lft forever

Run 'netplan try' (didn't even make any changes to the configuration) and the keepalived addresses disappear never to return, the affected interfaces have:
5: eth4: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether ab:cd:ef:90:c0:e3 brd ff:ff:ff:ff:ff:ff
    inet 10.22.14.6/24 brd 10.22.14.255 scope global eth4
       valid_lft forever preferred_lft forever
    inet6 fe80::ae1f:6bff:fe90:c0e3/64 scope link
       valid_lft forever preferred_lft forever
7: eth3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether ab:cd:ef:b0:26:29 brd ff:ff:ff:ff:ff:ff
    inet 10.22.11.6/24 brd 10.22.11.255 scope global eth3
       valid_lft forever preferred_lft forever
    inet6 fe80::ae1f:6bff:feb0:2629/64 scope link
       valid_lft forever preferred_lft forever
9: eth2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether ab:cd:ef:b0:26:2b brd ff:ff:ff:ff:ff:ff
    inet 12.13.14.18/29 brd 12.13.14.23 scope global eth2
       valid_lft forever preferred_lft forever
    inet 12.33.89.19/29 brd 12.13.14.23 scope global secondary eth2
       valid_lft forever preferred_lft forever
    inet6 fe80::ae1f:6bff:feb0:262b/64 scope link
       valid_lft forever preferred_lft forever