For how long a node keep its key?

Question

just a simple question:

• for how long every server of the net keep its private ? Or when every server change the key ?

I ask this because if a hacker steal the keys of the entire network how long he can use the key ?

Answer 1

The key is considered valid for a timeframe like a month - that's my observation as a node operator I used to be some years ago. You can regenerate keys anytime just by cleaning the key folder and restarting Tor.