DNS Anycast blackhole DNS traffic

[#1]

Issue:

DNS Anycast with BFD disabled cause DNS service to be non-responsive during restart. which leads to the black-hole of DNS traffic. and if there are any ZRQ happening at the same time it increases the downtime.

Solution:

one fix is to enable BFD, but that will cause BGP to flap during every DNS service restart.

Is there a better way to fix it?

[#2]

the external DNS services is flapping ... which is effecting for services