Some time yesterday afternoon PST Google upgraded us from Postini (which
we used for spam filtering) to Google Apps. I was planning to do the
migration by hand over the winter holiday but it looks like I missed the
upgrade notice.
Unfortunately our post-migration configuration severely restricted the
volume of outbound mail we were allowed to send which resulted in the
loss of mail. At 23:10 UTC yesterday (the 16th) we exceeded our daily
limit and GMail started rejecting our messages. This lasted until 20:45
UTC today. The rejection messages used a 550 (permanent) status code,
which caused the messages to be dropped on our end.
During this time messages to the Wireshark and WinPcap mailing lists
were archived but not sent. Messages to personal addresses were dropped.
I've updated our Google Apps configuration to remove the delivery
restrictions and reconfigured the Wireshark and WinPcap mail servers to
retry delivery instead of dropping messages so this hopefully shouldn't
be a problem in the future.
My apologies for any inconvenience.