I have a lot of subdomains on azrhymes.com, eg. de.azrhymes.com, es.azrhymes.com, etc. (~20 subdomains) and all of them work (including some very new ones) except ru.azrhymes.com that responds 'we could not connect to server'. What could've gone wrong?
Details:
I'm behind cloudflare and recently enabled dnssec, using wildcard ssl certificates and tried both * and specific A records - no difference.
I use a standard digital ocean debian droplet server, ru is in AMS3 region.
I don't use any dns zones.
I also purged my local dns cache (dscacheutil -flushcache && sudo killall -HUP mDNSResponder
).
(Tested connectivity through google and yandex webmaster)
Update: ru.azrhymes.com works 1 out of 10 times - roughly. (I've changed A record ip to a different server, changed back and the problem now went away on my computer and on yandex webmaster, google webmaster still cannot find my sitemap. This does not look too comforting.)
What can I test?