[tor-dev] Unreachable hidden service by some clients

[Liste]

I was open some hidden service to do an experiment:
All work fine.
After a day all hidden service on a single server are unreachable from
another server used as client.
After some hous all hidden server become reachable.

Some time when the hidden services are unreachable, they return to work
when tor restart.

What's going on?
We are under attack?