Your system will need to be tuned in order to run properly. Your validator may not start without the settings below. Run the following commands in your machine: 
sudo bash -c "cat >/etc/sysctl.d/21-nexis-validator.conf <<EOF
# Increase UDP buffer sizes
net.core.rmem_default = 134217728
net.core.rmem_max = 134217728
net.core.wmem_default = 134217728
net.core.wmem_max = 134217728

# Increase memory mapped files limit
vm.max_map_count = 1000000

# Increase number of allowed open file descriptors
fs.nr_open = 1000000
EOF"

sudo sysctl -p /etc/sysctl.d/21-nexis-validator.conf
paste the following in your terminal next: 
LimitNOFILE=1000000
DefaultLimitNOFILE=1000000
once you are done with this, run the following 
sudo systemctl daemon-reload

sudo bash -c "cat >/etc/security/limits.d/90-nexis-nofiles.conf <<EOF
# Increase process file descriptor count limit
* - nofile 1000000
EOF"
Voila! You have tuned your system now to run Nexis Validators , make sure you close the terminal and start a new one after following this guide!