Comment 3 for bug 1910369

Sources of elements for disk image builder (dib):

https://github.com/openstack-charmers/octavia-diskimage-retrofit/tree/master/src/elements (openstack-charmers-specific elements shipped with the snap)
https://github.com/openstack/diskimage-builder/tree/master/diskimage_builder/elements (disk-image-builder-specific)
https://github.com/openstack/octavia/tree/master/elements (Octavia-specific: includes ipvsadmin and keepalived-octavia)

The right elements seem to be included into the virt-dib invocation:

https://github.com/openstack-charmers/octavia-diskimage-retrofit/blob/2dad8d8d2b6615f406ad7339d92c4c1a3a6557d0/src/retrofit/retrofit.sh#L106-L108
virt-dib ${DEBUG} \
# ...
    ubuntu-cloud-archive ubuntu-ppa \
    haproxy-octavia rebind-sshd no-resolvconf amphora-agent \
    sos keepalived-octavia ipvsadmin pip-cache certs-ramfs \
    ubuntu-amphora-agent tuning bug189583

Will look further.