If a relay matches at least one fingerprint, IPv4 address, or IPv6
address in the fallback whitelist, it can become a fallback. This
reduces the work required to keep the list up to date.
Closes ticket 28768.
Tor clients on 0.3.5.6-rc? and later will use a consensus that will become
valid up to 24 hours in the future.
Clients on 0.3.5.5-alpha? and earlier won't accept future consensuses.
Update the fallback expiry tolerance to match tor's checks.
Part of 28768, follow-up on 28591.
Tor clients will use a consensus that expired up to 24 hours ago.
Clients on 0.3.5.5-alpha? and earlier won't select guards from an expired
consensus, but they can still bootstrap if they have existing guards.
Update the fallback expiry tolerance to match tor's checks.
Part of 28768, follow-up on 24661.
Avoid selecting fallbacks that change their IP addresses too often.
Select more fallbacks by ignoring the Guard flag, and allowing lower
cutoffs for the Running and V2Dir flags. Also allow a lower bandwidth,
and a higher number of fallbacks per operator (5% of the list).
Implements ticket 24785.
This removes some redundant repeated lines.
Ticket 24681 will maintain the current fallback weights by changing
Tor's default fallback weight to 10.
Implements ticket 24679.
Increase the fallback stability requirement to 30 days.
When this was at 7 days, we chose far too many unstable fallbacks.
Decrease the guard flag requirement to 0.8.
When this was at 0.9, we lost too many fallbacks due to version upgrades.
(The running and v2dir flags ensure DirPorts are available to clients.)
Partial fixes to #20913.
Sometimes, the fallback generation script doesn't add attributes to the
fallbacks in the list. If this happens, log an error, and avoid selecting
that fallback.
This is a rare issue: it should not change selection behaviour.
Fixes issue #20945.
Exclude relays that have been down for 1 or more days from the fallback
candidate list.
When a relay operator has multiple relays, this prioritises relays that are
up over relays that are down.
Fixes issue #20926.
7 days is a tradeoff between the expected time between major Tor releases,
which is 6 months, and the number of relays with enough stability.
Relays whose OnionOO stability timer is reset on restart by bug #18050
should upgrade to Tor 0.2.8.7 or later, which has a fix for this issue.
Closes ticket #20880; maintains short-term fix in e220214 in tor-0.2.8.2-alpha.
