Discontinuation of Legacy NS1 and NS3 IP Addresses

Table of Contents

• What’s changing
• Timeline
• Am I impacted?
• How to verify if you’re impacted
• What about the brownouts?
• What you need to do
• Questions or concerns?

As part of our multi-year effort to modernize our DNS infrastructure and improve global resolution performance, we are officially retiring the legacy IP addresses associated with our NS1 and NS3 name servers. These IPs have already been replaced by our high-performance Cache Edge network, first introduced in 2023.

Following the expansion of our cache edge infrastructure in 2024 and the discontinuation of the legacy NS2 and NS4 IP addresses in June 2025, NS1 and NS3 are the final two name servers still pointing to the older infrastructure. The legacy IPs will be fully decommissioned on July 6, 2026.

What’s changing

The table below summarizes the IP addresses that will be deprecated, along with their replacements in the cache edge layer:

As part of this change, the canonical name server hostnames for NS1 and NS3 are also moving to dedicated edge domains:

• ns1.dnsimple.com → ns1.dnsimple-edge.com
• ns3.dnsimple.com → ns3.dnsimple-edge.io

The legacy ns1.dnsimple.com and ns3.dnsimple.com hostnames will continue to resolve after the migration, but they will point to the new edge infrastructure.

Timeline

Am I impacted?

There are three groups of customers affected by this migration, each with a different level of action required.

Group 1 — Domains registered with DNSimple

You do not need to do anything. If your domain is registered with DNSimple and delegated to our name servers, we will handle the migration for you automatically between May 1 and June 1, 2026. All registered domains will be fully migrated by June 26, 2026. For domains using vanity name servers, we will also update the glue records at the registry and the corresponding A/AAAA records in your zone.

If you independently maintain a copy of your zone at another DNS provider (not through DNSimple’s secondary DNS), you should update the NS records at that provider to reference ns1.dnsimple-edge.com and ns3.dnsimple-edge.io. The old ns1.dnsimple.com and ns3.dnsimple.com hostnames will continue to work, but updating ensures your configuration stays current.

Group 2 — Domains registered elsewhere with DNS hosted at DNSimple

We recommend self-migrating, but we will force-migrate you by June 12, 2026. If your domain is registered at another registrar but uses DNSimple for DNS, your delegation at that registrar currently points at ns1.dnsimple.com and/or ns3.dnsimple.com. You have two options:

• Self-migrate (recommended): at your registrar, update the delegation to use ns1.dnsimple-edge.com and ns3.dnsimple-edge.io instead. You can do this any time after May 1, 2026.
• Do nothing: by June 12, 2026, we will transparently update the A and AAAA records for ns1.dnsimple.com and ns3.dnsimple.com to point at the new edge infrastructure. Your delegation will continue to work without changes on your side.

Group 3 — Using vanity name servers with a domain NOT registered through DNSimple

You must self-migrate before July 6, 2026. If you use vanity name servers (for example ns1.yourdomain.com), the glue records at your registrar currently point at the legacy Cloudflare IPs. We cannot update glue records on your behalf — only your registrar can do that. If you take no action, your domains will stop resolving when the legacy IPs are decommissioned.

How to verify if you’re impacted

If you use a vanity name server, you can check whether your glue records are still on the legacy IPs by running:

dig +short ns1.yourdomain.com
dig +short ns3.yourdomain.com

If the response contains 162.159.24.4 or 162.159.26.4 (or the matching IPv6 addresses), you need to update your configuration before July 6, 2026.

For non-vanity setups, you can check which name servers your domain uses at its registrar — if they reference ns1.dnsimple.com or ns3.dnsimple.com, you fall under Group 1 or Group 2 and no action is strictly required.

What about the brownouts?

On June 15, 2026 and June 22, 2026 we will briefly pause answering queries on the legacy Cloudflare IPs. Any traffic still landing on the old infrastructure will temporarily fail, making it easy to identify configurations that still need attention. If you notice intermittent resolution failures on those dates, treat it as a strong signal that you still have glue records or delegations pointing at the legacy IPs and should complete your migration before July 15, 2026.

What you need to do

• Group 1 — registered with DNSimple: No action required. We’ll handle the migration between May 1 and May 29, 2026.
• Group 2 — hosted at DNSimple, registered elsewhere: Optional but recommended: update your delegation at your registrar to ns1.dnsimple-edge.com and ns3.dnsimple-edge.io any time after May 1, 2026. Otherwise, you will be migrated transparently on June 26, 2026.
• Group 3 — vanity name servers: Required: update the glue records at your registrar to the replacement IPs above before July 6, 2026.

You can always refer to the latest list of official DNSimple name servers here:

👉 DNSimple Name Server Reference

Questions or concerns?

If you have any questions or need help with the transition, don’t hesitate to reach out to our support team.

Thank you for being part of DNSimple as we continue to invest in speed, resilience, and the future of DNS.