# Do not consider loopback addresses as martian source or destination while routing
# - Docker with custom networks uses an embedded DNS server with address 172.0.0.11
# - Kubernetes pods mount the node resolv.conf, so they can't use a loopack address
# that is only reachable from the node.
#
# KIND rewrites the well-known docker DNS address 127.0.0.11 by a non-loopback address.
# The DNS traffic coming from a pod will have to route to a localhost address to be NATed,
# hence we have to enable route_localnet or pods DNS will not work.
# Kubernetes mitigates the possible security issue caused by enabling this option.
# ref: https://nvd.nist.gov/vuln/detail/CVE-2020-8558
net.ipv4.conf.all.route_localnet=1
