I’ve seen this and similar network related stuff like NTP not working or failing to acquire sunrise sunset times…
In the few cases that I have seen, I felt that it was related to failed DNS queries. I could ping the device and access it locally, but it was having trouble getting to internet sites. The problem usually arose if the network cable was disconnected/reconnected. But I never spent much time figuring it out. Power cycling the Vera has always resolved the problem for me.
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