Circuit failed to establish

Question

I'm trying to build my own circuits using stem:

These are three different error messages I get from time to time:

1. Circuit failed to be created: DESTROYED
2. Circuit failed to be created: TIMEOUT
3. Unable to reach ((7, 'Failed to receive SOCKS5 connect request ack.'))

Can someone explain what do these three error messages mean? (Plus when I try to built that same circuit again I get the error sometimes and sometimes it builds up?) Is there congestion on the network? / Or is there some other reason?

Answer 1

https://gitweb.torproject.org/torspec.git/tree/tor-spec.txt#n1167

10 -- TIMEOUT         (Circuit construction took too long)
...
11 -- DESTROYED       (The circuit was destroyed w/o client TRUNCATE)

My guess is that there's something wrong with how you're trying to build the circuits in the first place. Have a look at how ExitMap currently builds custom circuits.