On October 11, 2026, the DNS root is scheduled to change its key-signing key (KSK) for only the second time ever. This key anchors DNSSEC’s chain of trust, which lets DNS resolvers authenticate answers using cryptographic signatures. The change is called a KSK rollover. Validating resolvers need to trust the new key before the switch, as otherwise healthy websites could become unreachable.

When we wrote about the first root KSK rollover in 2018, we had seen resolvers lose their learned trust in the new key during software upgrades or moves between machines. Publishing the key well in advance was only part of the job. We also needed to know whether resolvers had retained it, and we couldn’t give users a practical way to check.

Most website operators do not need to make any changes for this rollover. If you run a DNSSEC-validating resolver, check that it trusts the new root key, KSK-2024, and follow your software vendor’s instructions to update its trust anchors if the key is missing. If you use Cloudflare for your domain's DNS or rely on 1.1.1.1 and Gateway DNS, you do not need to take any action — our systems already trust KSK-2024.

To check ahead of time, visit our rollover readiness test. It asks the resolver your browser uses whether it trusts the new key. The test uses RFC 8509: A Root Key Trust Anchor Sentinel for DNSSEC, which we’ve implemented in 1.1.1.1 ahead of the rollover.

New key, same algorithm

KSK-2017 and KSK-2024 both use RSA/SHA-256. The rollover replaces the key pair while keeping the same method for creating and verifying signatures.

In our 2018 post, we wrote that a successful rollover would open the door to discussing an algorithm change. Eight years later, the root still uses RSA.

What comes after October

The October 11 switch changes which KSK signs the root’s DNSKEY set. The rollover continues into 2027, when ICANN plans to revoke KSK-2017, remove it from the root zone, and delete its private key. Stopping a key from signing and removing trust in that key are separate steps.

ICANN has also proposed a future root algorithm rollover to ECDSA P-256. ECDSA produces smaller keys and signatures than the RSA algorithm used today. That proposal is separate from this October’s key replacement, and ECDSA is not a post-quantum algorithm.