Exploring JPM’s Quorum: 0.1

4 min readAug 21, 2017

This document describes my initial experiments trying to understand JPM’s Quorum, a flavour of the Go-Ethereum client.

On my machine I have multiple versions of go-ethereum (also known as geth or goethe) installed. I was fairly confident that when I issued the following terminal command:

geth — testnet — rpc — mine

What was being executed was the version of goethe that lives in my $GOPATH, i.e.:

/Users/s.matthew.english/go/src/github.com/ethereum/go-ethereum

Turns out- that is accurate.

For instance, even though I was in the quorum directory, the output of which geth was the one on my $GOPATH:

However…

What I wanted to do was to run the JPM’s quorum (a different version of goethe), which lives in a separate directory, namely:

/Users/s.matthew.english/clients/quorum/0.0_quorum/quorum

Finally, it is possible to specify on start-up which version of goethe is executed.

The first attempt I made was to try and edit /etc/paths, like so:

subl /etc/paths

Note: subl refers to Sublime Text, you can also do that just as well with nano or vim.

At first my /etc/path looked like this:

/usr/local/bin
/usr/bin
/bin
/usr/sbin
/sbin

I changed it to this:

/Users/s.matthew.english/clients/quorum/0.0_quorum/quorum/
/usr/local/bin
/usr/bin
/bin
/usr/sbin
/sbin

But that didn’t work!

So I asked a question on StackOverflow [0], which also failed to yield any interesting information.

Let me back-up for a second — the reason that I was trying to change /etc/paths was because of the $PATH hierarchy. When you call terminal commands to start some program, the program referenced in the directory that comes earlier in your $PATH is the one that get executed. So the reason the version of geth (goethe) that lived in my $GOPATH was running — as opposed to the quorum version (despite the fact that I was sitting inside of the quorum directory), was because my $PATH looked like this:

Notice that my `quorum` directory comes at the end.

Here you can see that the directory with quorum:

/Users/s.matthew.english/ConsenSys/PegaSys/clients/quorum/0.0_quorum/quorum/

comes last in the $PATH.

Finally I was able to move the quorum directory to the front of my $PATH by appending the following code snippet to my “bash profile”, which in my case is actually ~/.zshrc:

#-------------------------------------------------------------
# attempt to add some Quorum stuff...
#-------------------------------------------------------------export PATH=$HOME/ConsenSys/PegaSys/clients/quorum/0.0_quorum/quorum/build/bin:$PATH

This needs to come at the end of your bash profile. If you think (and look) closely you can see that what is actually happening is, at last — right before the bash profile is consummated — I slip the quorum directory up front and append the rest of the $PATH behind it ;)

So by virtue of that neat trick we’re able to get the quorum directory to the front as we can see here:

Proper directory comes first: nothing changes!

Why then does the $GOPATH variant of geth show up when we issue the which geth command?

Simple — we’d forgotten to actually build the executable binary file!

After cloning the qurorum repo and configuring a correct fork configuration [1], I’d never actually went to the base of my quorum project and issued the command make geth which is what creates the runnable program file in the sub-directory /build/bin.

Having done completed that step, I also added the further-specified sub-directory structure to the $PATH — I’m not 100% sure that you actually need to add that level of detail, maybe your machine is smart enough to figure it out — so finally I had this as my $PATH:

Next thing I did was fire up my local version of quorum like so:

Exploring JPM’s Quorum: 0.1

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Written by S. Matthew English