Stacks 2.0 Testnet Wiki

What information to collect for debugging?

Make sure you enable debug logs and backtraces. Something like BLOCKSTACK_DEBUG=1 RUST_BACKTRACE=1 cargo testnet start --config your-config.toml should work
It might be easier to direct the log output to a file. Something like BLOCKSTACK_DEBUG=1 RUST_BACKTRACE=1 cargo testnet start --config miner.toml >> miner.log 2>&1 should work
The on-disk chain state can be useful for debugging. Either set working_dir under the node section of your configuration, or look for the most recently created directory under /tmp of the form /tmp/stacks-*

Known issues: