Bisq seed nodes serve as static gateways for Bisq clients to get connected to Bisq’s dynamic P2P network.

In this doc, you will find information about:

  • what a seed node is and how it works

  • the duties of a seed node operator

  • the benefits of being a seed node operator

  • how to get a seed node up and running

  • where to get in touch

What is a Bisq seed node

Bisq uses a highly anonymous and dynamic P2P network for communications between Bisq clients. In order to get access to the network, the Bisq network features always-up Bisq clients with a static addresses: seed nodes. They have 2 main tasks:

  1. Deliver the peer addresses of other dynamic network peers

  2. Deliver the initial P2P network data like open offers, mailbox messages and arbitrators

  3. Deliver the initial DAO state

Being the gateways to the Bisq P2P network, seed nodes are among the first nodes a Bisq client connects to on each startup. Therefore,

  • seed nodes face a heavy load and are therefore operated on servers offering a high level of reliability and better connectivity than a Bisq client for home use.

  • A bad seed node can have a substantial impact on the Bisq network. A Bisq user may encounter anything from a longer startup time of her Bisq client (which is inconvenient but not critical) to missing messages sent to her by a trading partner or arbitrator while her Bisq client has been offline (which can lead to disputes, failed trades, bad reputation and even blocking of the Bisq client).

All in all, seed nodes play a vital role in the Bisq network. They allow users easy access to the Bisq network and therefore must be kept online and available at all times. Without the seed nodes, a new Bisq client would not find its way into the network, at least not without manual intervention. Bad seed nodes can make it harder for a new client to join the network.

Seed node operators

Being a seed node operator brings along duties and benefits making it worthwhile.

Duties of the seed node operator

The operator of a seed node needs to:

  • find yourself a deputy in case you are not available (travel, holiday, others, …​). Usually, one of the developers is there to help. Just inform them on your setup and all is good.

  • keep the server up and running, including patching and hardening the operating system

  • keep the seed node software up to date

  • keep an eye on Bisq’s communication channels for updates, issues, countermeasures, etc (see Getting in Touch)

  • keep an eye on the logs of the seed node and the operating system, and act if something shows up

  • if necessary, report and escalate (see Getting in Touch)

  • set up a bond of 20000 BSQ (twenty-thousand BSQ) to get the privilege to run a seed node. In case of severe failure of service, the bond gets confiscated (burned).

  • create a monthly report here

Compensation

A seed node operator has the right to:

  • file a compensation request over 200 BSQ for setting up a seed node

  • file a monthly compensation request. We define 50 BSQ per month as an appropriate compensation per seed node per month.

With the advent of the DAO and the subsequent need of an additional 300GB of disk space for the Bitcoin full node, the numbers here are currently under discussion. Until new figures are decided on, state your expenses for running the server and add the 50 BSQ on top to get your sum for compensation.

Getting in Touch

Bisq uses Slack to communicate via chat. As a seed node operator, you are required to

  • subscribe to the Bisq Slack channel bisq-seednode and bisq-monitor

  • the bisq-seednode channel is the place where updates, issues, countermeasures, heads-ups, etc are discussed. If you encounter a problem with your seed node and cannot solve it by yourself, this is the place to report to (with a specific question, logs, etc). A developer will get back to you.

  • the bisq-monitor channel is the place where issues with seed nodes are reported, either manually or by our monitoring service. If your seed node is mentioned for having an issue, you are required to react.

  • please be responsive when addressed

System requirements for hosting machine

  • Min. 4 GB of RAM

  • 400 GB of disk space

  • 2 TB network traffic

  • Uptime of > 99.9%

  • > 10000 file handles available (check ulimit -Sn)

And please try to stay away from cheap hosting providers! They tend to not care about QOS, the hardware is slow, they occasionally even turned a service off without warning - ask us how we know…​

Get a seed node up and running

You can run your seed node in many ways. The guide you are currently reading applies to a (debian-based) unix system with systemd available. Furthermore, we assume that only one seed node is operated per host. Please be aware that the guide is only a guide and not a step-by-step copy-and-paste how-to, as we ignore for example the need for the occasional root access and file permissions, swap, general opsec, among other things. In case your host differs from our reference system, we are sure you can handle yourself.

There are four pieces to the puzzle of successfully running a seed node:

  • a Bitcoin full node

  • the Bisq seednode itself and

  • system health reports

and last but not least, the all-important firewall.

Firewall

Although every port that is to be used only by localhost clients should be hardened by configuration and source code already, we recommend whitelisting stuff that is actually needed. Here is an example on how to configure iptables accordingly (the config drops any incoming connections except connection from localhost, SSH and responses.):

iptables -P INPUT DROP && iptables -A INPUT -i lo -j ACCEPT && iptables -A INPUT -p tcp --dport 22 -j ACCEPT && iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT

Make sure you execute all iptables commands at once! Executing only the first one is going to kick you out of your ssh session and does not let you back in.

Bitcoin Node

Start by setting up a user for the bitcoin core stuff.

useradd -r -m bitcoind
cd /home/bitcoind

Download the Bitcoin Core binaries here to this directory, unpack it and, for updating convenience, create a symlink to the necessary binaries (so you only have to change the symlink on update):

tar xzf bitcoin-0.18.0-x86_64-linux-gnu.tar.gz
ln -s bitcoin-0.18.0/bin/bitcoind bitcoind
ln -s bitcoin-0.18.0/bin/bitcoin-cli bitcoin-cli

Create a systemd service file bitcoind.service in the systemd service path for your operating system (something like /usr/lib/systemd/system/) and adapt it to your needs. We recommend to create a user bitcoind for service hardening reasons. In the end, it should look like

[Unit]
Description=Bitcoind
After=network.target

[Service]
ExecStart=bitcoind -daemon \
                   -printtoconsole \
                   -nodebuglogfile \
                   -pid=/home/bitcoind/.bitcoin/bitcoind.pid
ExecStop=/home/bitcoind/bitcoin-cli stop

Type=forking
PIDFile=/home/bitcoind/.bitcoin/bitcoind.pid
Restart=on-failure

User=bitcoind
Group=bitcoind

PrivateTmp=true
ProtectSystem=full
NoNewPrivileges=true
PrivateDevices=true
MemoryDenyWriteExecute=true

[Install]
WantedBy=multi-user.target

Create a file /home/bitcoind/.bitcoin/bitcoin.conf that contains

txindex=1
listen=0
rpcallowip=127.0.0.1
rpcuser=YOUR_USER_NAME
rpcpassword=YOUR_PW
blocknotify=sh ~/.bitcoin/blocknotify.sh %s

and another file /home/bitcoind/.bitcoin/blocknotify.sh that contains

#!/bin/sh
echo $1 | nc -w 1 127.0.0.1 5120

and make it executable (chmod +x /home/bitcoind/.bitcoin/blocknotify.sh).

Finally, enable and start the service

systemctl enable bitcoind.service
systemctl start bitcoind.service

and observe the logs

journalctl --unit bitcoind --follow

and check if everything works as expected.

Bisq Seed Node

Start by getting OpenJDK 10 up and running.

For getting the Bisq binaries, we recommend cloning the Bisq Git repository and compiling the code on your server. This way, you have precise control over what version you want to deploy. Furthermore, updating is very simple, just pull the changes, recompile and restart your service.

Furthermore, we recommend creating a user bisq in group bisq for service hardening reasons and using the bisq user’s home directory to:

useradd -r -m bisq
cd /home/bisq
git clone git@github.com:bisq-network/bisq.git
cd bisq
./gradlew build -x test

Create a systemd service file bisq-seednode.service (or copy the one shipped with bisq $bisqdir/seednode/bisq-seednode.service) in the systemd service path for your operating system (something like /usr/lib/systemd/system/) and adapt it to your needs.

In the end, your file should look something like

[Unit]
Description=Bisq Seed Node
After=network.target

[Service]
Environment="JAVA_OPTS=-Xms512M -Xmx2000M -Dcom.sun.management.jmxremote -Dcom.sun.management.jmxremote.port=6969 -Dcom.sun.management.jmxremote.rmi.port=6969 -Dcom.sun.management.jmxremote.ssl=false -Dcom.sun.management.jmxremote.authenticate=false"
ExecStart=/home/bisq/bisq/bisq-seednode --appName=bisq-seednode --nodePort=8000 --userDataDir=/home/bisq/ --maxConnections=30 --fullDaoNode=true --rpcUser=YOUR_USER_NAME --rpcPassword=YOUR_PW --rpcPort=8332 --rpcBlockNotificationPort=5120

Restart=on-failure

User=bisq
Group=bisq

PrivateTmp=true
ProtectSystem=full
NoNewPrivileges=true
PrivateDevices=true
MemoryDenyWriteExecute=true

[Install]
WantedBy=multi-user.target

Note that the jmxremote JVM arguments are later used for monitoring the service, the rpc arguments are there to get the seed node hooked to the bitcoin service. Make sure that the YOUR_USER_NAME and YOUR_PW placeholders match the configuration of Bitcoin Node.

Enable and start the seed node by

systemctl daemon-reload
systemctl enable bisq-seednode.service
systemctl start bisq-seednode.service

Keep an eye on the logs and see if everything works as expected:

journalctl --unit bisq-seednode --follow

In case you are about to take over a seed node from someone else, you need to manually import their onion address and private key.

In /home/bisq/.local/share/bisq_seednode/btc_mainnet/tor/hiddenservice/, replace the files

hostname
private_key

with the ones you received from the former seed node operator. Restart your service

systemctl restart bisq-seednode.service and again, observe the logs and make sure everything works as expected.

Finally, we ask you to prepare for the worst. Go to /home/bisq/.local/share/bisq-seednode/btc_mainnet/tor/hiddenservice/ and backup the files

hostname
private_key

to a secure location. In case your server loses the original files during a crash, you can recover easily by following the steps for taking over a seed node. All other data like the db or the keys directory are not relevant for the seed node.

System health reports

Since seed nodes are such a crucial part of the Bisq network, we require periodic health reports to our monitor. Since the monitor only accepts plain TCP connections for incoming data, we have to accept a bit of overhead to keep the monitor from being flooded with unauthorized input.

In order to successfully report to the monitor, we need to create a TCP reverse proxy local to your host that can authenticate to the monitor. For this guide, we go with nginx, if you prefer another reverse proxy, we are sure you can handle yourself.

First of all, if you have not already, install nginx on your system.

Then proceed to creating the SSL certificate that is later used to authenticate against the monitor:

cd /etc/nginx
openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout /etc/nginx/cert.key -out /etc/nginx/cert.crt

Use ON = bisq.network, OU = seednodes and CN = <your seed nodes onion address here (without the ".onion" part)> for certificate creation. The onion address can be found in the hostname file mentioned before.

Configure the reverse proxy with clientssl enabled. You can simply append the snippet below to your /etc/nginx/nginx.conf file:

stream {
	log_format basic '$remote_addr [$time_local] '
	                 '$protocol Status $status Sent $bytes_sent Received $bytes_received '
	                 'Time $session_time';

	error_log syslog:server=unix:/dev/log;
	access_log syslog:server=unix:/dev/log basic;

	server {
		listen 2003;
		allow 127.0.0.1;
		deny all;
		proxy_pass monitor.bisq.network:2003;
		proxy_ssl on;

		proxy_ssl_certificate /etc/nginx/cert.crt;
		proxy_ssl_certificate_key /etc/nginx/cert.key;

		proxy_ssl_session_reuse on;
	}
}

Start your nginx and observe the logs to see if everything works as expected:

systemctl restart nginx
journalctl --unit nginx --follow

Once you are satisfied, proceed on installing collectd and use this collectd config to start from. Fill in the onion address of your seed node

Hostname "<ONION_ADDRESS again without the ".onion">"

and adjust the interface, df, disk plugins so that they match your setup (and thus, report meaningful metrics).

Start your collectd service and check the logs for any issues:

systemctl restart collectd
journalctl --unit collectd --follow

Once you are satisfied, go ahead and report your client certificate (/etc/nginx/cert.crt) to the bisq-seednode channel (see Getting in Touch). The monitoring team will then whitelist your host and you can enjoy your metrics at https://monitor.bisq.network.