Technical write-ups are moving to Habr (Russian-only) — starting with the case of the vanishing IPv6

A quick housekeeping note. This blog stays focused on what's happening in SEO and GEO — trends, algorithm updates, how search actually works. Purely technical write-ups — infrastructure, networking, server-side debugging — now go to a specialized outlet instead: my Habr profile.

Today's piece there is worth knowing about even if you don't read Russian. A client — a large online publication — had lived for three months with the explanation "it's Russian network-level filtering, nothing to be done." Their site kept vanishing for search and AI crawlers: 89 days straight of a fluctuating failure rate, anywhere from 0.2% to 78%. The explanation was convincing precisely because it couldn't be checked by hand.

There turned out to be three causes, all on the same server, none of them network filtering: an IPv6 address that existed only in DNS, nginx listening on IPv6 for the wrong server block, and a whole-country geo-block buried in the hosting panel's firewall. That last one came down with a single console command — which is itself the tell: a real network-level block can't be fixed with one command on your own box.

Read the full case on Habr → (Russian only)

Apologies in advance — Habr is Russian-only for me. If a particular piece interests you, email me and I'll send you an English version.

Maxim Safianov

I work at the intersection of technical SEO and software engineering: helping sites stay visible for classic search and AI answers alike, and building the Python tooling that automates it.