Migrating (Signed) Zones to PowerDNS

This chapter discusses various migration strategies, from existing PowerDNS setups, from existing unsigned installations and finally from previous non-PowerDNS DNSSEC deployments.

From an existing PowerDNS installation

To migrate an existing database-backed PowerDNS installation, ensure you are running at least PowerDNS 3.3.3 and preferably 3.4 or newer.

If you run an older version of PowerDNS, please upgrade to 3.4 and apply all the changes in database schemas as shown in the upgrade documentation.

Warning

Once the relevant backend-dnssec switch has been set, stricter rules apply for filling out the database! The short version is: run pdnsutil rectify-all-zones, even those not secured with DNSSEC! For more information, see the Handling DNSSEC signed zones.

To deliver a correctly signed zone with the DNSSEC Defaults, invoke:

pdnsutil secure-zone ZONE

To view the DS records for this zone (to transfer to the parent zone), run:

pdnsutil show-zone ZONE

For a more traditional setup with a KSK and a ZSK, use the following sequence of commands:

pdnsutil add-zone-key ZONE ksk 2048 active rsasha256
pdnsutil add-zone-key ZONE zsk 1024 active rsasha256
pdnsutil add-zone-key ZONE zsk 1024 inactive rsasha256

This will add a 2048-bit RSA Key Signing Key and two 1024-bit RSA Zone Signing Keys. One of the ZSKs is inactive and can be rolled to if needed.

From existing non-DNSSEC, non-PowerDNS setups

It is recommended to migrate to PowerDNS before securing your zones. After that, see the instructions above.

From existing DNSSEC non-PowerDNS setups, pre-signed

Industry standard signed zones can be served natively by PowerDNS, without changes. In such cases, signing happens externally to PowerDNS, possibly via OpenDNSSEC, ldns-sign or dnssec-sign.

PowerDNS needs to know if a zone should receive DNSSEC processing. To configure, run pdnsutil set-presigned ZONE.

If you import presigned zones into your database, please do not import the NSEC or NSEC3 records. PowerDNS will synthesize these itself. Putting them in the database might cause duplicate records in responses. zone2sql filters NSEC and NSEC3 automatically.

Warning

Right now, you will also need to configure NSEC(3) settings for pre-signed zones using pdnsutil set-nsec3. Default is NSEC, in which case no further configuration is necessary.

From existing DNSSEC non-PowerDNS setups, live signing

The pdnsutil tool features the option to import zone keys in the industry standard private key format, version 1.2. To import an existing KSK, use

pdnsutil import-zone-key ZONE FILENAME ksk

replace ‘ksk’ by ‘zsk’ for a Zone Signing Key.

If all keys are imported using this tool, a zone will serve mostly identical records to before, with the important change that the RRSIG inception dates will be different.

Note

Within PowerDNS, the ‘algorithm’ for RSASHA1 keys is modulated based on the NSEC3 setting. So if an algorithm=7 key is imported in a zone with no configured NSEC3, it will appear as algorithm 5!

Secure transfers

PowerDNS supports secure DNSSEC transfers as described in draft-koch-dnsop-dnssec-operator-change. If the direct-dnskey option is enabled the foreign DNSKEY records stored in the database are added to the keyset and signed with the KSK. Without the direct-dnskey option DNSKEY records in the database are silently ignored.