[tor-bugs] #9206 [Tor]: 'Guard' flags only assigned to first nodes started in a private Tor network

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#9206: 'Guard' flags only assigned to first nodes started in a private Tor network
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     Reporter:  karsten  |      Owner:
         Type:  defect   |     Status:  needs_review
     Priority:  normal   |  Milestone:  Tor: 0.2.5.x-final
    Component:  Tor      |    Version:
   Resolution:           |   Keywords:  tor-auth tor-relay simulation
Actual Points:           |  testing
       Points:           |  Parent ID:
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Comment (by robgjansen):

 Replying to [comment:14 ln5]:
 > Replying to [comment:13 robgjansen]:
 > > We were at one point but it must have gotten removed. Should we be
 using these? Would this allow us to specify guard flags?
 >
 > No. I'm asking because since getting guard depends not only on
 (weighted) uptime, but also on whether you're Fast or not, which is
 influenced by either bandwidth files or, if those are not present, what
 the relays say themselves.
 >
 > My suggested solution, based on a Chutney use case, was to make relays
 brag about high speed which in a network where dir auths don't have
 bandwidth files will make them all Guards.
 >

 Doesn't this come with the unintended consequence of messing up path
 selection in other ways?

 > The reason that I dropped the "brute force solution" (forcing flags on
 relays by configuring dir auths to just set the bloody flag, goddamit) is
 that in Shadow, there seems to be no way of refer to a relay before the
 network is started.

 We can refer to them by domain name or nickname (the 'id' attribute of the
 'node' element in the hosts.xml files), but you're correct that we cannot
 refer to them by fingerprint because its dynamically generated.

 > I wasn't pondering the idea of adding a dir auth configuration option
 making _all_ relays Guards, Stable or whatever. Would that be useful to
 you, Rob?

 In my experience, the "start the relays that we want to get the guard flag
 first" approach *usually* results in the correct relays getting the guard
 flags. ATM, I don't see a clear benefit in other approaches that don't
 *guarantee* correct assignment.

 In testing mode, perhaps each relay could tell the dirauths which flags it
 wanted, and the dirauth could just blindly agree. Though, the code
 complexity is probably high, and I understand that this sort of feature
 could be considered unclean and a nightmare to maintain. So, maybe the
 'start the guards first' approach is good enough?

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/9206#comment:15>
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