Consul Service Discovery for HAProxy

blog20210601-01.hcl

datacenter = "dc1"
server = true
data_dir = "/var/lib/consul/"
bind_addr = "192.168.50.21"
client_addr = "192.168.50.21"
bootstrap = true
bootstrap_expect = 1

ui_config {
    enabled = true
}

enable_syslog = true
log_level = "INFO"

blog20210601-02.sh

$ /usr/bin/consul agent -config-dir=/etc/consul.d/

blog20210601-03.sh

$ sudo add-apt-repository -y ppa:vbernat/haproxy-2.4
$ sudo apt update
$ sudo DEBIAN_FRONTEND=noninteractive apt install -y haproxy

blog20210601-04.sh

$ wget https://github.com/haproxytech/dataplaneapi/releases/download/v2.3.0/dataplaneapi_2.3.0_Linux_x86_64.tar.gz
$ tar -zxvf dataplaneapi_2.3.0_Linux_x86_64.tar.gz
$ sudo cp build/dataplaneapi /usr/local/bin/
$ sudo chmod +x /usr/local/bin/dataplaneapi

blog20210601-05.yaml

config_version: 2
name: haproxy1
dataplaneapi:
  host: 192.168.50.20
  port: 5555
  user:
  - name: dataplaneapi
    password: mypassword
    insecure: true

blog20210601-06.cfg

program api
  command /usr/local/bin/dataplaneapi -f /etc/haproxy/dataplaneapi.yaml
  no option start-on-reload

blog20210601-07.sh

$ sudo systemctl restart haproxy

blog20210601-08.sh

$ curl -u dataplaneapi:mypassword \
       -H 'Content-Type: application/json' \
       -d '{
             "address": "192.168.50.21",
             "port": 8500,
             "enabled": true,
             "retry_timeout": 10
           }' http://192.168.50.20:5555/v2/service_discovery/consul

blog20210601-09.hcl

datacenter = "dc1"
server = false
data_dir = "/var/lib/consul/"
bind_addr = "192.168.50.22"
retry_join = ["192.168.50.21"]
enable_syslog = true
log_level = "INFO"

blog20210601-10.json

{
  "service": {
    "name": "web",
    "port": 80
  }
}

blog20210601-11.sh

$ consul services register ./web.json

blog20210601-12.cfg

backend consul-backend-192.168.50.21-8500-web
  server SRV_V2u4y 192.168.50.22:80 check weight 128
  server SRV_1NQXA 127.0.0.1:80 disabled weight 128
  server SRV_DWcAP 127.0.0.1:80 disabled weight 128
  server SRV_IIcqg 127.0.0.1:80 disabled weight 128