seed-node-daemon.md

Running a seed node as a daemon

WARNING: These docs are out of date!

This document presents some steps to be able to run a bisq seed node as an unattended daemon in a GNU/Linux server with a traditional System V init.

Before you start

We assume that you have already configured a bisq seed node to run in a computer. You will need to upload the seed node code and configuration to the server:

• The code is contained in the build/libs/bisq-seednode.jar file which is produced when building Bisq with ./gradlew build.
• The seed node configuration is the bisq_seed_node_HOST_PORT directory under ~/.local/share (Unix), %APPDATA% (Windows) or ~/Library/Application Support (Mac OS X).

Dedicated user

In order to avoid security risks, it is highly recommended that you create a dedicated user in the server to run the seed node daemon, and that you forbid other users to access its files, for instance:

# adduser bsqsn
# chmod go-rwx ~bsqsn

Place the jar file where the bsqsn user can read it and tag it with bisq's version number (to allow running several instances of mutually incompatible versions), e.g. ~bsqsn/bisq-seednode.jar. Copy the configuration directory to the ~bsqsb/.local/share directory.

Testing the seed node

You need to check that the seed node can actually run in your system. For instance, if you are using version 0.4.4 and your seed node's Tor address is 1a2b3c4d5e6f7g8h.onion:8000, try to run this as the bsqsn user:

$ java -jar ~bsqsn/bisq-seednode.jar 1a2b3c4d5e6f7g8h.onion:8000 0 50

Please check error messages if it fails to run. Do note that you will need OpenJDK and OpenJFX in the server. In Debian-like systems you may install the needed dependencies with:

# apt-get --no-install-recommends install openjfx

After the node runs successfully, interrupt it with Control-C.

Init script

To allow the daemon to start automatically on system boot, use the attached init script. First edit it and change its configuration variables to your needs, especially SN_ADDRESS, SN_JAR and SN_USER. In the previous example, the values would be:

SN_ADDRESS=1a2b3c4d5e6f7g8h.onion:8000
SN_JAR=~bsqsn/bisq-seednode.jar
SN_USER=bsqsn

Put the customized script under /etc/init.d using a name without extensions (e.g. bisq-sn), make it executable, add it to the boot sequence and finally start it:

# cp /path/to/bisq-sn.init.sh /etc/init.d/bisq-sn
# chmod a+rx /etc/init.d/bisq-sn
# update-rc.d bisq-sn defaults
# service bisq-sn start

Executing service bisq-sn status should report that the process is running.

Cron script

The attached Cron script can be used to check the seed node daemon periodically and restart it if it is using too much memory (RSS at the time, may change to VSS later).

To enable this check, edit the script and change the MAX_RSS_MiB to whatever limit (in MiB), copy it to /etc/cron.hourly and make it executable:

# cp /path/to/bisq-sn.cron.sh /etc/cron.hourly/bisq-sn
# chmod a+rx /etc/cron.hourly/bisq-sn

The check will be run every hour. For more sophisticated checks, use a proper monitor like Monit.

Monitor script

The attached monitor script can be used to watch several seed nodes by connecting to them over Tor, and report by email if there were any failed connection attempts. The script uses the torify and nc tools, so make sure that you have the tor and some netcat package installed in your system. Also make sure that it is able to send messages using the mail utility.

To enable the monitor, first edit the script and set the email addresses you want to report to in REPORT_TO_EMAILS; if you want to specify the set of seed nodes to check, change the value of SEED_NODES. Then copy the script to /etc/cron.hourly and make it executable:

# cp /path/to/monitor-bisq-sn.cron.sh /etc/cron.hourly/monitor-bisq-sn
# chmod a+rx /etc/cron.hourly/monitor-bisq-sn

Since this script requires no special permissions, you may instead want to run it from a normal user's crontab (e.g. the bsqsn user above).