Common Issue When Running a Full Node

How to monitor your full node syncing process?

  • You could see the current height of full node, visit localhost:26657/status
  • You could see the log info you log under your $BNCHOME. Monitor the output with:
tail -f $BNCHOME/bnc.log

Common Issues

If you start running a full node from scratch, you are likely to encounter the following issues:

AppHash Confliction

  • Error Log
panic: Tendermint state.AppHash does not match AppHash after replay. Got XXXXXXX, expected 251DF08F2BA7824F0875D33992CF03EA35106DDD34B3A9FE4EFA0B73CDD2FE14

This error is caused by a consensus issue and thus bnbchaind will panic.

  • Solution

To solve this issue, make sure that you have downloaded the correct genesis file. If you replaced the genesis file, then you need to do a node reset. To reset node:

rm $BNCHOME/data

rm $BNCHOME/config/priv_validator_key.json

Then, start again.

Peer connection error

  • Error log:
E[2019-04-17|23:52:24.069] Connection failed @ recvRoutine (reading byte) module=p2p peer=[aea74b16d28d06cbfbb1179c177e8cd71315cce4@](http://aea74b16d28d06cbfbb1179c177e8cd71315cce4@{[](} err=EOF
E[2019-04-17|23:52:24.070] Stopping peer for error module=p2p peer="Peer{MConn{[](} aea74b16d28d06cbfbb1179c177e8cd71315cce4 out}" err=EOF

This error is caused that the handshake between peers is not successful.

  • Solution

To solve this problem, you need to make sure node_key.json is under $BNCHOME/config and nodes will try re-connect automatically, so this issue should not persist.

Connection Timeout

  • Error log
Dialing failed module=pex addr=2c1fa9c1698961da38d8cd50da9fe8b4bc433c50@ err="dial tcp i/o timeout" attempts=3
  • Solution

Check your internet connection and make sure it is stable.

Out of memory

  • Error Log
fatal error: out of memory
  • Solution

Your machine must have more than 16 GB memory, otherwise, it will not handle db restoration during state sync.

No priv_validator_state.json after reset

  • Error log
open /Users/.bnbchaind/data/priv_validator_state.json: no such file or directory
  • Solution

Delete both priv_validator_state.json file and data folder if you want to reset your full node.