DNS ‘Flag Day’ will mark the beginning of large scale EDNS implementation

• Many DNS software and service providers have planned to end DNS resolver workarounds after February 1st.
• This move aims to curb non-compliant sites which do not adhere to the latest DNS standards.

Come February 1, any website that does not adhere to newer DNS standards will have their existing workarounds stopped by their DNS providers. February 1 -- known as ‘DNS Flag Day’, will see DNS providers incorporate massive changes with regard to standards such as Extension Mechanisms For DNS (EDNS) for all websites.

This is to curb growing, complex DNS software troubling the DNS system on the whole. “To ensure further sustainability of the system it is time to end these (non-compliant) accommodations and remediate the non-compliant systems. This change will make most DNS operations slightly more efficient, and also allow operators to deploy new functionality, including new mechanisms to protect against DDoS attacks,” says the official DNS Flag Day website.

Non-compliant sites will be unavailable

Once DNS providers start updating their systems from February 1, non-compliant sites will be rendered invalid. “This change will affect domains hosted on authoritative servers which do not comply either with original DNS standard from 1987 (RFC1035) or the newer EDNS standards from 1999 (RFC2671 and RFC6891). Non-compliant domains may become unreachable through these services.”

Therefore, domain owners are suggested to check whether they are DNS/EDNS compliant on the DNS Flag Day site. If failures occur, firewalls blocking EDNS traffic, or older DNS servers might be the most likely reasons. In addition, the authoritative servers might also require technical changes. All in all, migration to EDNS standards will take a brief period to settle around DNS across the world.

Notable organizations such as Cisco, Cloudflare, Facebook, Google, Quad9 have supported this initiative.