System Management

Users and Groups

# Add user
# for Debian
adduser -d /qortal_home -s /bin/bash -c "Qortal Node" qortal
# for Ubuntu
addgroup qortal
adduser --home /qortal_home --ingroup qortal --shell /bin/bash --gecos "Qortal Node" qortal
adduser --gecos "Bastillion-Jetty" jetty
## for System only
adduser --system  --gecos "Bastillion-Jetty" --group jetty  

# Delete user
deluser --remove-home jetty
# Delete group
delgroup jetty

Network

/etc/network/interfaces:

auto eth0
iface eth0 inet static
address 10.1.1.201
netmask 255.255.255.0
network 10.1.1.0
broadcast 10.1.1.255
gateway 10.1.1.254
dns-nameservers 10.1.1.254
dns-search my.domain.com

Apply the settings

sudo service networking reload