[tor-bugs] #18580 [Tor]: exit relay fails with 'unbound' DNS resolver when lots of requests time-out

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#18580: exit relay fails with 'unbound' DNS resolver when lots of requests time-out
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 Reporter:  Dhalgren  |          Owner:
     Type:  defect    |         Status:  new
 Priority:  Medium    |      Milestone:
Component:  Tor       |        Version:  Tor: 0.2.7.6
 Severity:  Major     |     Resolution:
 Keywords:            |  Actual Points:
Parent ID:            |         Points:
 Reviewer:            |        Sponsor:  None
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Comment (by Dhalgren):

 On the unbound-users thread Aaron Hopkins was tremendously helpful and led
 me to what I think is the correct analysis and resolution of this issue:

 https://unbound.net/pipermail/unbound-users/2016-April/004301.html

 TL;DR version

 `Unbound` /etc/resolv.conf
    options timeout:5 attempts:1 max-inflight:4096 max-timeouts:100

 `named` /etc/resolv.conf
    options timeout:5 attempts:1 max-inflight:4096 max-timeouts:100

 Possibly, even probably max-timeouts:1000000 is better but I'd like hear
 from a Tor developer on whether completely inhibiting the "down resolver"
 state in eventdns (even when the resolver is in fact down) is a good idea
 or not.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/18580#comment:12>
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