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Re: vanishing HSDIR flags

On Aug 21, 2010, at 3:35 PM, Scott Bennett wrote:

Hi Sebastian,
    Thanks for responding.
On Sat, 21 Aug 2010 15:17:19 +0200 Sebastian Hahn <mail@xxxxxxxxxxxxxxxxx >
On Aug 21, 2010, at 1:49 PM, Scott Bennett wrote:

   Yesterday (Friday) the number of relays given HSDir flags by the
directory authorities was reduced by a bit more than 50% from only a
day earlier. My node, MYCROFTsOtherChild, was and still is among the
bereft.  This same situation happened a couple of weeks ago, also
affecting my node. That time the flag reappeared several hours after
I first noticed what had happened.  This time the flag is still
   It is not obvious to me why the HSDir flag has been stripped from
so many relays, especially relays that have, like mine, been up and
running for weeks since the last restart. Has a bug been triggered in
the authority code?

Apparently enough authorities have upgraded to See
the changelog for details.

Yes, I see that entry now in the Changelog, although I don't see the reasoning behind it. HSDir requests differ in just about every imaginable
way from ordinary directory requests.  The protocol is different, the
HSDir entry format is different, the request frequency is lower by orders of magnitude, the requests are--or at least as I recall--intended to be handled over internal circuits rather than via a DirPort, and so on. I just don't see any reason to tie the HSDir service to the presence/ absence
of a DirPort.
    Also, given the switch from decentralized traffic distribution to
centralized traffic distribution in recent tor versions, nodes advertising throughput capacities of, say, 49 KB/s or less (I don't really know where the curve becomes steeper) get little use already. Given that DirPort is ignored when the advertised throughput capacity is less than 50 KB/ s, tying
HSDir service to the presence/absence of an active DirPort means that
relatively unused relays cannot even help out with handling the trivial traffic volume of HSDir requests. Doesn't that seem rather counterproductive?

The issue is that there is a bug in relays that checks for the DirPort to
be enabled before it answer directory requests, including hsdir
stuff. Before a complete fix for that is developed, the short-term
workaround to make hidden services more stable is to make remove
the nodes without a dirport from the dht. As soon as a fix is
developed, the authorities can start assigning the flag again based on
Tor version.