provider "openstack" {
  cloud = "lab-admin"
  use_octavia = true
}

# data "template_file" "user_data" {
#   template = file("user-data.txt")
# }

data "template_file" "user_data" {
  template = < /tmp/debug
EOF
}

variable "http_instance_names" {
  type = set(string)
  default = ["www1", "www2"]
}

resource "openstack_compute_instance_v2" "http" {
  for_each    = var.http_instance_names
  name        = each.key
 #name = "www${count.index + 1}"
 #count = 2
 image_name = "Ubuntu 20.04 minimal"
 flavor_name = "m1.small"
 key_pair = "lab-key"
 security_groups = ["default"]
 user_data = data.template_file.user_data.rendered

 network {
   name = "demo-net"
 }
}

data "openstack_networking_network_v2" "network_1" {
  name = "demo-net"
}

data "openstack_networking_subnet_v2" "subnet_1" {
  name = "demo-subnet"
  network_id = data.openstack_networking_network_v2.network_1.id
}

# Create loadbalancer
resource "openstack_lb_loadbalancer_v2" "http" {
  name          = "demo-lb1"
  vip_subnet_id = data.openstack_networking_subnet_v2.subnet_1.id
}

# Create listener
resource "openstack_lb_listener_v2" "http" {
  name            = "demo-lb1-http-listener"
  protocol        = "TCP"
  protocol_port   = 80
  loadbalancer_id = openstack_lb_loadbalancer_v2.http.id
  #depends_on      = [openstack_lb_loadbalancer_v2.http]

  insert_headers = {
    X-Forwarded-For = "true"
    X-Forwarded-Proto = "true"
  }
}

# Create pool
resource "openstack_lb_pool_v2" "http" {
  name        = "demo-lb1-http-pool1"
  protocol    = "TCP"
  lb_method   = "ROUND_ROBIN"
  listener_id = openstack_lb_listener_v2.http.id
  #depends_on  = [openstack_lb_listener_v2.http]
}

# Add member to pool
resource "openstack_lb_member_v2" "http1" {
  for_each      = var.http_instance_names
  address       = openstack_compute_instance_v2.http[each.key].access_ip_v4
  protocol_port = 80
  pool_id       = openstack_lb_pool_v2.http.id
  subnet_id     = data.openstack_networking_subnet_v2.subnet_1.id
  #depends_on    = [openstack_lb_pool_v2.http]
}

# Get floating IP
resource "openstack_networking_floatingip_v2" "floatingip_1" {
  pool = "public"
}

# Associate floating IP to LoadBalancer
resource "openstack_networking_floatingip_associate_v2" "floatip_1" {
  floating_ip = openstack_networking_floatingip_v2.floatingip_1.address
  port_id = openstack_lb_loadbalancer_v2.http.vip_port_id
}

output "LoadBalancer_IP" {
  value = "http://${openstack_networking_floatingip_v2.floatingip_1.address}"
}

TERMINATED_HTTPS loadbalancer

Container
https://hub.docker.com/_/haproxy

Configuration
/tmp/haproxy/haproxy.cfg

global
  maxconn 4096
  #stats timeout 30s
  #debug

defaults
  log global
  mode http
  option httplog
  option dontlognull
  timeout connect 5000
  timeout client 50000
  timeout server 50000
  log 127.0.0.1 local0
  #option httpchk

frontend frontend1
  bind :80
  mode http
  use_backend backend1

backend backend1
  mode http
  balance roundrobin
  option httpchk GET / HTTP/1.1
  http-check expect status 400
  server www1 172.17.0.2:80 check
  server www2 172.17.0.4:80 check
  server www3 172.17.0.6:80 check

listen stats 
  bind :9000
  mode http
  stats enable
  stats hide-version
  stats realm Haproxy\ Statistics
  stats refresh 60s
  stats show-node
  stats auth haproxy:password
  stats uri /

Deploy

docker run -d --name haproxy -v /tmp/haproxy:/usr/local/etc/haproxy:ro -p 8080:80 -p 9000:9000 haproxy:latest
docker logs -f  haproxy