Linux running multiple BOINC clients

Running multiple copies of the BOINC client at the same time, may utilize the GPU more efficiently.
Check the GPU usage by using NVIDIA X Server (must have NVIDIA drivers installed) or PSensor.
Check the CPU usage by using System Monitor. Make sure the CPU usage is below 100% ,to leave room for the CPU to feed the GPU.

Setup multiple BOINC clients:

First create extra boinc folders:
In Ubuntu, click on “Search your computer” and in the search fiels type ‘terminal’ and select the terminal icon.
In the terminal type:
sudo mkdir /var/lib/boinc2
sudo mkdir /var/lib/boinc3
sudo nautilus

Open /var/lib/boinc-client/cc_config.xml with a text editor ( in nautilus use the right mouse button) and add the following.

<cc_config>
<options>
<use_all_gpus>1</use_all_gpus>
<allow_multiple_clients>1</allow_multiple_clients>
</options>
</cc_config>

If there already is a <cc_config></cc_config> block, do not add another one, but past the part including <options></options> inside the existing <cc_config></cc_config> block.

Next copy cc_config.xml using nautilus to /var/lib/boinc2 and /var/lib/boinc3
Next copy rpc_gui_auth.cfg using nautilus to /var/lib/boinc2 and /var/lib/boinc3

If you haven’t done this already:
In  /var/lib/boinc-client/cc_config.xml, open the file ‘remote_host.cfg‘ and at the end of the file enter the IP address (or addresses on a new line) of your BoincTasks computer. It is best to setup a fixed IP address on the computer running BoincTasks.
Next copy /cc_config.xml using nautilus to /var/lib/boinc2 and /var/lib/boinc3

Now fire up the 2 new BOINC clients:

In the terminal type:
Warning: When you copy and paste the commands, thinks might look OK.
But that might NOT be the case.
If you get an error, manually replace the – with the – on the keyboard.

sudo /usr/bin/boinc −−daemon −−allow_multiple_clients −−gui_rpc_port 31418 −−dir /var/lib/boinc2
sudo /usr/bin/boinc −−daemon −−allow_multiple_clients −−gui_rpc_port 31420 −−dir /var/lib/boinc3

The rpc port must NOT be in use by any computer on the local network.

If you want this to happen every time the system boots.
Edit the cron tasks:
cron sudo crontab -e
Use e.g. @reboot /usr/bin/boinc −−daemon −−allow_multiple_clients −−gui_rpc_port 31418 −−dir /var/lib/boinc2

Setting up BoincTasks and BoincTasks Js.

Read this.

*Tested on a Ubuntu machine, commands and locations for other Linux OS may vary.