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HOWTO: Setup an Agent

This guide is for those interested in running a Syscoin Bridge Agent node. Agents build the Syscoin SuperblockChain on Ethereum by hashing 60 Syscoin blocks together and storing this as 1 Superblock in the Bridge Superblocks smart contract

The chain activity can be seen here


  1. Syscoin node on Linux box VPS
  2. ETH fund (18 ETH recommended, >3 ETH minimum)

Setup Guide

This guide assumes the following:

  1. user "ubuntu"
  2. default .syscoin data directory (~/.syscoin)
    (please change the names accordingly)

After setting up your Syscoin node, do the following:

Create a new Eth address through Syscoind's Geth

$ sysgeth.nod account new -datadir .syscoin/geth

If you're planning your node to perform both roles (challenger & submitter), create a second address:

$ sysgeth.nod account new -datadir .syscoin/geth

Send some ETH to the addresses ( > 3 ETH needed for each; at least 9 on each address is recommended)

Install Dependency

$ sudo apt-get install default-jdk maven

Download sysethereum-agents

$ git clone
$ cd sysethereum-agents

Edit the configuration file in data/sysethereum-agents.conf (see below)
$ nano data/sysethereum-agents.conf 

Compile agent

$ mvn compile 
$ mvn package

Run agent.  The first argument is the location to the sysethereum-agents.conf file

$ java -Dsysethereum.agents.conf.file=/home/ubuntu/sysethereum-agents/data/sysethereum-agents.conf -Dhttps.protocols=TLSv1.2,TLSv1.1,TLSv1 -jar target/sysethereum-agents-1.0-jar-with-dependencies.jar 

OR run it with screen so you can disconnect from ssh session.
You may have to install screen first:
$ sudo apt-get install screen

$ screen java -Dsysethereum.agents.conf.file=/home/ubuntu/sysethereum-agents/data/sysethereum-agents.conf -Dhttps.protocols=TLSv1.2,TLSv1.1,TLSv1 -jar target/sysethereum-agents-1.0-jar-with-dependencies.jar 
hit ctrl+A and D to detach screen so it'll run in the background

you can resume the screen with this command
$ screen -r

Mandatory Fields

The configuration file has many fields. Only the following are needed:


general.purpose.and.send.superblocks.address and syscoin.superblock.challenger.address

These two addresses should be different. These are your Geth wallet address(es) mentioned above where you sent >3 ETH to each.

This field should be /home/ubuntu/.syscoin or the full path to the syscoin data directory


The following 3 fields should match the RPC configuration in your syscoin.conf file for Syscoin Core: syscoinrpc.user, syscoinrpc.password and syscoinrpc.url_and_port
A cookie will be generated if rpcuser and rpcpasswords are not set in syscoin.conf; the rpcuser becomes "cookie" and rpcpassword can be found by running ps - ef | grep syscoin to look at what's passed to relayer. The format will be "__cookie:[rpcpassword]" after "--sysrpcusercolonpass"
syscoinrpc.url_and_port is most likely "http://localhost:8370". Change the 8370 if you use a different RPC port.

secondary.url address

Please head to and create an account there.
Then create a new project and find a drop down beside ENDPOINT then select Mainnet.
Take that URL and prefix it with "https://" use it for secondary.url.
Example: secondary.url = ""

Challenger and/or Submitter

These two configurations can be toggled to choose what role to play; submitter, challenger or both.
syscoin.superblock.submitter.enabled = true
syscoin.superblock.challenger.enabled = true

Optional Fields

Agent email notification

Email notification can be set up as follows:

agent.mailer.enabled = true

agent.mailer {
    enabled: true,
    smtp {
        # See
        host: "",
        port: 587,
        username: "[email protected]",
        password: "verystrongpassword",
        transportStrategy: "SMTP_TLS"  # Supported values: "SMTP", "SMTP_TLS" and "SMTPS"
    challenge.notifier {
        trigger: "ANY_BLOCK",  # Supported values: "MY_BLOCK", "ANY_BLOCK"
        from: "[email protected]",
        to: "receivinge[email protected]",
        subject: "Syscoin agent challenges superblock(s)!"

The simplest way is to create and use a gmail account.
Change the username and password above to those of your gmail.
Change the challenge.notifier from address to this account.
Head to with your new gmail account and enable "less secure apps".
When you run it the first time, check your new gmail account and you should see some security alerts for a log in attempt (most likely from your VPS's region). Allow it, then restart your agent. You should then be able to receive notifications.


With this smtp gmail you can also setup

git clone
cd sysethereum-agent-monitor
npm i

Edit config.json to configure the monitor for your environment.

Config Parameters:
interval - (seconds) how often to check system statuses. - SMTP host.
smtp.auth.user - SMTP username, leave blank for no auth.
smtp.auth.pass - SMTP password, leave blank for no auth.
smtp.port - SMTP server port. - Syscoin RPC host.
syscoin.user - Syscoin RPC username.
syscoin.pass - Syscoin RPC password.
syscoin.port - Syscoin RPC port.
explorer_url - URL to Syscoin block explorer that utilizes BCF Explorer API. No trailing slash.
nottify_address - Email address which notifications will be sent.

Updated 10 months ago

HOWTO: Setup an Agent

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