Purpose

This page shows you how to launch an Loom Testnet node from the jump start.

Download stable version of loom

wget https://downloads.loomx.io/loom/linux/extdev-stable/loom
chmod +x loom

Download jump start archive

There are two available locations where you can download it from, USA or Singapore. Choose the location closest to you. The Singapore location is automatically replicated from the USA location so it might be a while before it becomes available when we update the archive.

United States

Singapore

Extract archive

tar xfvz extdev-plasma-us1-jump-start.tar.gz

Generate unique config

mkdir blank
cd blank
cp ../loom-jump-start/loom.yml .
../loom init
cp chaindata/config/{priv_validator.json,node_key.json} ../loom-jump-start/chaindata/config/
cd ../loom-jump-start

Start the node

NOTE: Check the open files limit on your system before starting the node! See Open Files Limit.

Now, let's start the node by running:

../loom run --persistent-peers tcp://[email protected]:46656,tcp://[email protected]:46656,tcp://[email protected]:46656,tcp://[email protected]:46656

Finally

The non-validator node will now sync with the validator nodes. Status can be queried at http://localhost:46658/rpc/status

Make loom run as a service on Ubuntu 16.04 (Optional)

Create /etc/systemd/system/loom.service

[Unit]
Description=Loom
After=network.target

[Service]
Type=simple
User=<user that runs loom>
WorkingDirectory=<working directory of loom>
ExecStart=<path to loom>/loom run --persistent-peers tcp://[email protected]:46656,tcp://[email protected]:46656,tcp://[email protected]:46656,tcp://[email protected]:46656
Restart=always
RestartSec=2
StartLimitInterval=0
LimitNOFILE=500000
StandardOutput=syslog
StandardError=syslog

[Install]
WantedBy=multi-user.target

Reload the config

systemctl daemon-reload

To make it run on boot

systemctl enable loom.service

To start/stop/restart

systemctl (start/stop/restart) loom.service

To look at logs (method 1)

tail -f /var/log/syslog

To look at logs (method 2)

sudo journalctl -u loom.service -f

Open Files Limit

When using systemd, the open files limit is taken care of by the LimitNOFILE directive. It will not, however, be applied when running loom manually.

For system-wide limit

Add the following lines to /etc/sysctl.conf

fs.file-max=500000

To activate it immediately:

sudo sysctl -p

To check whether it is active:

cat /proc/sys/fs/file-max

For specific user

Add lines to /etc/security/limits.conf

username        hard nofile 500000
username        soft nofile 500000

Note: The user needs to re-login to have it active

To check whether it is active:

# check soft limit
ulimit -Sn

# check hard limit
ulimit -Hn