check current value
sysctl net.ipv4.ip_forward
set to enabled
sudo sysctl net.ipv4.ip_forward=1
Persist across boots
sudo nano /etc/sysctl.conf
# Uncomment the next line to enable packet forwarding for IPv4 #net.ipv4.ip_forward=1
reference:
sysctl net.ipv4.ip_forward
sudo sysctl net.ipv4.ip_forward=1
sudo nano /etc/sysctl.conf
# Uncomment the next line to enable packet forwarding for IPv4 #net.ipv4.ip_forward=1