49 lines
1.5 KiB
Markdown
49 lines
1.5 KiB
Markdown
---
|
|
title: Dev mode
|
|
sort_key: B
|
|
---
|
|
|
|
Geth has a development mode which sets up a single node Ethereum test network with a number of options optimized for developing on local machines. You enable it with the `--dev` argument.
|
|
|
|
Starting geth in dev mode does the following:
|
|
|
|
- Initializes the data directory with a testing genesis block
|
|
- Sets max peers to 0
|
|
- Turns off discovery by other nodes
|
|
- Sets the gas price to 0
|
|
- Uses the Clique PoA consensus engine with which allows blocks to be mined as-needed without excessive CPU and memory consumption
|
|
- Uses on-demand block generation, producing blocks when there are transactions waiting to be mined
|
|
|
|
You can specify a data directory to maintain state between runs using the `--datadir` option, otherwise databases are ephemeral and in-memory:
|
|
|
|
```shell
|
|
$ mkdir test-chain-dir
|
|
$ geth --dev --datadir test-chain-dir console
|
|
```
|
|
|
|
Once geth is running in dev mode, you can interact with it in the same way as when geth is running in other ways.
|
|
|
|
For example, create a test account:
|
|
|
|
```shell
|
|
> personal.newAccount()
|
|
```
|
|
|
|
Then transfer ether from the coinbase to the new account:
|
|
|
|
```shell
|
|
> eth.sendTransaction({from:eth.coinbase, to:eth.accounts[1], value: web3.toWei(0.05, "ether")})
|
|
```
|
|
|
|
And check the balance of the account:
|
|
|
|
```shell
|
|
> eth.getBalance(eth.accounts[1])
|
|
```
|
|
|
|
If you want to test your dapps with a realistic block time use the `--dev.period` option when you start dev mode:
|
|
|
|
```shell
|
|
geth --dev --dev.period 14 console
|
|
```
|