[tor-bugs] #3825 [Tor Hidden Services]: Hidden service unavailable even though I know its up

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#3825: Hidden service unavailable even though I know its up
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 Reporter:  atoruser             |          Owner:  rransom         
     Type:  defect               |         Status:  needs_review    
 Priority:  major                |      Milestone:                  
Component:  Tor Hidden Services  |        Version:  Tor: unspecified
 Keywords:                       |         Parent:                  
   Points:                       |   Actualpoints:                  
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Changes (by rransom):

  * status:  assigned => needs_review


Comment:

 Replying to [comment:4 atoruser]:
 > Even after upgrading the hidden service and the client to 0.2.2.32 this
 problem continues to happen.

 We already knew that Tor clients would have trouble connecting to hidden
 services which can't connect to the client's rendezvous point before the
 client times out (see #1297).  I suggested upgrading the hidden service
 server to Tor 0.2.2.32 in the hope that, if that had been the problem, the
 adaptive circuit-build-timeout code on the 0.2.2.x branch would allow your
 hidden service to reach more of its clients more quickly.  But it looks
 like that wasn't your problem at all.

 > Here is the log of my application trying to connect to the hidden
 service which I know is up.
 >
 > Sep 11 08:31:05.805 [notice] Tried for 120 seconds to get a connection
 to [scrubbed]:25. Giving up. (waiting for circuit)
 (13 lines deleted)
 > Sep 11 09:25:46.337 [notice] Based on 1000 circuit times, it looks like
 we don't need to wait so long for circuits to finish. We will now assume a
 circuit is too slow to use after waiting 10 seconds.
 > Sep 11 09:26:22.987 [notice] Tried for 120 seconds to get a connection
 to [scrubbed]:25. Giving up. (waiting for circuit)
 > Sep 11 09:27:01.373 [notice] Tried for 120 seconds to get a connection
 to [scrubbed]:25. Giving up. (waiting for circuit)
 > Sep 11 09:43:20.397 [notice] Based on 1000 circuit times, it looks like
 we need to wait longer for circuits to finish. We will now assume a
 circuit is too slow to use after waiting 11 seconds.
 > Sep 11 09:45:02.015 [notice] Tried for 120 seconds to get a connection
 to [scrubbed]:25. Giving up. (waiting for circuit)
 (3 lines deleted)
 >
 > At 10:06 I restarted the tor process and then it connected fine.

 It looks like a relay serving as one of your hidden service's introduction
 points when your client first fetched the HS descriptor at around 08:31
 became unreachable.  Tor clients currently do not detect that they are
 failing to use an intro point unless the failure occurs after the client
 has finished building a circuit to it; if they cannot build a circuit to
 the intro point at all, they will never give up on using that intro point
 to connect to the hidden service.  See
 [https://gitweb.torproject.org/rransom/tor.git/shortlog/refs/heads/bug3825a-v4
 bug3825a-v4] ( `https://git.torproject.org/rransom/tor.git bug3825a-v4` )
 for a fix for this client-side bug.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/3825#comment:5>
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