ValueError: {'code': -32000, 'message': 'already known'}

Question

I am performing a transaction to send an ERC20 and I keep getting this error:

ValueError: {'code': -32000, 'message': 'already known'}

I'm assuming this means that this transaction is already in the mempool or something? Looking for some clarifications though.

score 3 · Accepted Answer · answered May 04 '21 at 20:45

3

Partial answer...

I'm assuming this means that this transaction is already in the mempool or something?

// ErrAlreadyKnown is returned if the transactions is already contained
// within the pool.
ErrAlreadyKnown = errors.New("already known")

But it's not immediately clear from the code what conditions have to be met for this error to be set, so it's difficult to suggest a solution.

answered May 04 '21 at 20:45

Richard Horrocks

1

I think this is pretty much it. Just wanted others to be aware of what is going on when they run into this error. – Patrick Collins May 04 '21 at 20:54
I think the nonce can be used to prevent the error, and it needs to be checked against the most recent older nonce. – Cristofor Jun 27 '21 at 17:27

score 0 · Answer 2 · answered Jan 27 '23 at 06:35

I was getting this error using github.com/ethereum/go-ethereum

First, make sure you are using the right nonce in the tx

nonce, err := client.PendingNonceAt(context, someAddress)

Then, make sure you are passing the right context to all your methods, including the one above

2 Answers2