Just drop the port range field from the icmp outbound rule in your request.

i tried to launch a firewall from terraform as well, but it doesn’t really work yet. terraform’s documentation basically copies digitalocean’s documentation verbatim, so this is definitely a bug with digitalocean’s api.

the only way i could get it to work (creating a firewall from scratch using terraform), was to setup the firewall config as you would normally (using all does work for port_range on inbound rules). comment out the entire outbound_rule block. run terraform plan then terraform apply and it will create the firewall. add the three outbound rules from the digitalocean web console. run terraform refresh then uncomment the outbound_rule block. if your outbound rules are like any other firewall, terraform plan should be green now with no changes to be made.

also worth noting - any inbound rules created from terraform using port_range = "all" will need to be changed back to port_range = "0" once the rule has been created to make terraform happy again.