Hello Milan,
We don't provide any tool for such a conversion. But it should be
possible
to do it manually. The .key file is simple. Just use `keymgr <zone>
dnskey`.
The .private file is more tricky. You have to somehow convert Knot's
.pem file
and set timestamp and other items.
Daniel
On 2019-03-04 10:05, Milan Jeskynka Kazatel wrote:
  Hello community,
 can I somehow convert stored certificates for a signed zone to BIND
 format?
 My use case is to change used topology for authoritative servers. I´m
 manage existing zones in Knot, now I would like to transfer it to BIND
 and use existing certificates for signing it on BIND due to DS records
 in parent zones. The knot will be reconfigured as a slave.
 Is it possible to achieve it?
 Thanks.
 --
 Smil Milan Jeskyňka Kazatel