tor server thinks IP address changed twice when it did not change

[Scott Bennett <bennett@xxxxxxxxxx>]

     This a.m. my miserable ISP did its daily thing of forcing a disconnection
and re-login of the router here, and as usual, a different IP address was
assigned.  The relevant entries in /var/log/messages are:

Nov 21 06:30:17 hellas INADYN[1162]: I:INADYN: IP address for alias 'mars.thruhere.net' needs update to '66.225.36.39'
Nov 21 06:30:17 hellas INADYN[1162]: I:INADYN: Alias 'mars.thruhere.net' to IP '66.225.36.39' updated successful.

     Within a few minutes, tor noticed, too:

Nov 21 06:40:38.063 [notice] Your IP address seems to have changed. Updating.
Nov 21 06:40:43.366 [notice] Self-testing indicates your ORPort is reachable from the outside. Excellent. Publishing server descriptor.
Nov 21 06:40:59.339 [notice] Self-testing indicates your DirPort is reachable from the outside. Excellent.
Nov 21 06:41:45.066 [notice] Performing bandwidth self-test...done.

     However, a while later and completely unnecessarily, tor did this:

Nov 21 07:56:52.311 [notice] Your IP address seems to have changed. Updating.
Nov 21 07:56:53.403 [notice] Self-testing indicates your ORPort is reachable from the outside. Excellent. Publishing server descriptor.
Nov 21 07:57:55.025 [notice] Your IP address seems to have changed. Updating.
Nov 21 07:57:59.599 [notice] Self-testing indicates your ORPort is reachable from the outside. Excellent. Publishing server descriptor.
Nov 21 07:58:02.279 [notice] Self-testing indicates your DirPort is reachable from the outside. Excellent.
Nov 21 07:58:16.929 [notice] Have tried resolving or connecting to address '[scrubbed]' at 3 different places. Giving up.
Nov 21 07:58:16.965 [warn] We just marked ourself as down. Are your external addresses reachable?

     Meanwhile, the connection was good the whole time, tor traffic was being
relayed, and the IP address remained unchanged since the previously noted
event.  In the slightly more than an hour that has passed since the weirdness
occurred between 07:56 and 07:59, tor has continued to run, answering directory
requests and passing traffic.
     So it looks like there is a bug involved here, and it apparently does
not depend upon starting up with no cached-descriptors* files.  Does anyone
working on tor development recognize these symptoms?  Or is this something new?


                                  Scott Bennett, Comm. ASMELG, CFIAG
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