"stable" flag voting differences - tor-relays

27 Oct 2013


      I observed an interesting behavior in the
authority votes regarding relay stability
and am curious if anyone can comment.
Have a new relay, about ten days old.
Relay is marked
Fast Guard Running Stable Valid
One 10 minute network outage three days ago
and then a 68 minute outage one day ago
for repair.  Overall about 4680 seconds down
over the last week, and if one uses a
646220 second timeframe per this post
https://lists.torproject.org/pipermail/tor-relays/2013-July/002255.html
It works out to about 99.27% uptime,
which seems within the 98% threshold
quoted in the posting.
What was interesting was that
Faravahar
   gabelmoo
   maatuska
   tor26
   urras
all immediately removed the "stable" flag when
the relay came back online after maintenance,
while
dannenberg
   moria1
left the stable flag in place.  The two
remaining authorities
dizum
   turtles
have never set the stable flag due to heavy
link congestion between AS286/AS3265
for 'dizum' and congestion within AS6461
for 'turtles'.
Then exactly 24-hours after the end of the
outage the five naysayers turned the
stable flag back on.
Mainly a point of curiosity, but I'd guess
from this that the first five authorities
listed above are using a much shorter
window for evaluating stability while
the second two are using the seven-day
window.  I couldn't find per-authority
logging of this category of information
so it's hard to know.
Perhaps it's relevant that the node was
removed from the consensus directory 
briefly immediately after the outage ended.
Finally it is interesting that 'dizum' and
'turtles' have set the "guard" flag even
though they consider the relay unstable.
This is a recent development.  Earlier
the two impaired-path authorities had
the guard flag set off.