Setting up an Ethereum node on the Rinkeby testnet

Warning: this worked for me on macOS as of August 2017. Over time you can expect some/most/all of the information here to have changed.

There are several testnets, a number of them old/deprecated. The latest seem to be Kovan and Rinkeby. Kovan seems to work only with Parity while Rinkeby seems to work only with geth.

You will need to install geth first.

I mostly followed this guide.

I tried first the experimental light mode but I got errors, so I tried with the full mode. Not a big deal at this moment because the size on disk is below 1GB and it took around one hour to download/build with a 2011 macbook Air.

I prefer to make the data directory explicit (where the blockchain files will be stored), so I first create one on a disk of my choice. Also I will work from that directory, so I will assume all commands are entered from it.

$ mkdir /path/to/rinkeby
$ cd /path/to/rinkeby

intitalise with genesis block

$ curl -O $ geth --datadir=. init rinkeby.json

load blockchain 

$ geth --networkid=4 --datadir=. --ethstats='yournode:Respect my authoritah!' --bootnodes=enode://a24ac7c5484ef4ed0c5eb2d36620ba4e4aa13b8c84684e1b4aab0cebea2ae45cb4d375b77eab56516d34bfbd3c1a833fc51296ff084b770b94fb9028c4d25ccf@ --cache=1024

Wait. You will see the INFO message "Block synchronisation started" then many INFO lines starting with "Imported...". Sync is in progress... 

  • Note the 1GB cache, you can use less or more depending on your available memory
  • Network id 4 corresponds to the Rinkeby chain
  • Blockchain data will be stored in geth/

Check blockchain sync progress

While the node is up & running (the above command) you can get info about the blockchain sync progress (among other data) through the JavaScript console. In another terminal window type:

$ cd /path/to/rinkeby
$ geth attach ipc:geth.ipc

At the ">" prompt you can type, e.g.

> eth
> eth.syncing
> adm
> adm.peers

You can double check you are seeing the right data progress by looking at the last block at home page.

Note that the "NOTE...Importing..." messages include a number parameter which is the block being processed.

Getting free (worthless) ether for testing

Create a testing account

Create an account, enter password, get its address (account data will be saved to keystore/):

$ geth --datadir=. account new
...(enter password):..
Address: {559b0e5a899d9ef4c04ee35ccbefab2e6d7f06da}

That is the address I got. In order to use the faucet & get ether into this account, first create a github gist with just the hash in it (remember to prepend with "0x"). In my case:

Now use your gist URL in the faucet feature at

I requested 3 ETH, then I searched etherscan with my address to verify I got them:

Next verification step would be to verify that locally we also get the correct balance.

We first verify it is taking the accounts we created (files in keystore/)

> eth.accounts
["0x559b0e5a899d9ef4c04ee35ccbefab2e6d7f06da", "0x62c8681441620cb0574fcee27d6085529067b8da"]

The first one (index 0) is the one I got my 3 ETH, let's see if they are on our local blockchain (balance for account 0):

> web3.fromWei(web3.eth.getBalance(web3.eth.accounts[0]));


Now we may keep using geth, or a wallet for a nice UI.

Share a Mercurial repository on github (macOS)

Local macOS configuration

Python & Mercurial

This was tested on macOS El Capitan, with Pyhton 2.7 and Mercurial 4.2.2

Install Hg-Git

You will need the Hg-Git Mercurial plugin.

It can be installed with Python's package installer pip.

Install pip first:

$ wget
$ python

Install Mercurial (eventually) & Hg-Git:

$ sudo pip install mercurial
$ sudo pip install hg-git

Enable the extension:

$ vi ~/.hgrc:

hggit =

SSH key for github

create SSH key (details)

  • ssh-keygen -t rsa -b 4096 -C ""

add it to your github account (details)

  • $ pbcopy < ~/.ssh/
  • Github: Settings -- SSH / GPG Keys -- New SSH key -- paste clipboard

Configure & share repository

create empty github repository

  • create on github
  • copy its URL
configure local empty repository
$ mkdir myrepo
$ cd myrepo
$ hg init

set username & include github URL as default 
$ vi .hg/hgrc

username = Someone Example

default = git+ssh://

Push & pull

Upload local changes to github

hg addremove
hg commit
hg bookmark -r default master
hg push

Integrate locally changes made on github

hg pull -u

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This is an intensive program of 4 months (June to September), at the end of which we expect to get funding (65% of the projects got it in past editions and we believe ours is among the best :-).

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Current team members have expertise in business, marketing and backend development. We need to cover the graphical design/UI/front end area.

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Email Round Trip Monitoring

If you administer an email server as I do, it's very useful to have an automated monitoring system that checks often that it works properly.

My first try on any new feature I want to add to my non-fatally-critical systems is to use an external service, specially if it can be done for free. Whereas there is a number of server monitoring services, most don't include roundtrip email monitoring, at least on their free plan. 

The only one I found to include it is...