How to change default account in private ethereum network

Question

I have created 5 account in my network. My default account is account 0. I want to make a transaction and some operations on account 3 so I want to set the default account to account 3. How to make account 3 as default?

Answer 1

First list the accounts:

> eth.accounts

NOTE: Even though you have mentioned that you want to set account 3 as default, selecting the account from the list displayed from the above command is important because there is a chance that the index of accounts is changed. 

Now to set the default account to account 3, you the following command:

> miner.setEtherbase(web3.eth.accounts[3])