Collateral blocking on a shared CDN IP
Roskomnadzor blocks not only domains but IP addresses. Large CDNs (Cloudflare and others) place thousands of sites on one shared IP — if a single “prohibited” neighbour is blocked by IP, everyone on that address goes dark. Symptom: your domain is NOT in the registry but is unreachable from Russia and resolves into a shared CDN range. /rkn flags a hint when the IP falls into a known CDN range. The fix is a dedicated IP or hosting with a Russian presence.
Below: details, example, related guides, FAQ. This is diagnostic guidance for resource owners using the public EAIS registry — not circumvention advice.
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Details
- IP blocking is collateral by nature: the operator-side filter drops the whole address without distinguishing which domain is “at fault”.
- Shared-IP CDN is the main source of the problem: a single Cloudflare anycast IP may host thousands of domains owned by different parties.
- Diagnostic signal: the domain is absent from the EAIS registry but unreachable from Russian nodes, and its IP belongs to a shared CDN range.
- How to confirm: get the IP via dig, check membership in a CDN range, and test availability specifically from RU nodes (not your own network).
- What an owner can do: request a dedicated IP from the CDN/host, consider a Russian CDN or a mirror deployment, and monitor availability from RU nodes — this is diagnosis and an infrastructure fix, not circumvention.
Example
# 1. Which IP the domain resolves to
dig +short example.com A
# 104.21.x.x / 172.67.x.x → shared Cloudflare range (high collateral risk)
# 2. Who owns the IP (CDN or dedicated address)
whois 104.21.0.1 | grep -iE 'orgname|netname|cloudflare'
# 3. Registry + CDN hints in one request
https://enterno.io/en/rkn
# 'domain clean + IP in CDN range + unreachable from RU' = collateral
# 4. Fix: a dedicated IP
# Cloudflare: a plan with Dedicated IP; or a host with a Russian PoPRelated
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Frequently Asked Questions
How do I tell collateral from a direct block?
With a direct block your domain/URL is in the EAIS registry. With collateral, the registry is clean for your domain but the IP belongs to a shared CDN range and the site is unreachable from Russia. Confirm both facts.
Will changing DNS or CDN node help?
No, if you stay on the same shared IP. What helps is a dedicated IP address (or a provider/CDN with a Russian presence and separate addressing). This is an infrastructure fix, not block circumvention.
Could my own site cause collateral for neighbours?
Yes — if your content is listed and blocked by IP, neighbours on the same address suffer too. Another reason to watch your domain’s status and keep a dedicated IP for critical services.
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