dir-spec is wrong about how authorities decide HSDir flag
dir-spec.txt says
"HSDir" -- A router is a v2 hidden service directory if it stores and
serves v2 hidden service descriptors and the authority managed to connect
to it successfully within the last 24 hours.That sure makes it sound like "was found reachable at least once in the past day".
The actual test is in dirserv_thinks_router_is_hs_dir(): if it's Running now, and its uptime appears to be >= 25 hours.
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