Chapter 26. Load balancing on RHOSP

Procedure

1. From a command line, create an Octavia load balancer that uses the Amphora driver:

   $ openstack loadbalancer create --name API_OCP_CLUSTER --vip-subnet-id <id_of_worker_vms_subnet>

   You can use a name of your choice instead of API_OCP_CLUSTER.

2. After the load balancer becomes active, create listeners:

   $ openstack loadbalancer listener create --name API_OCP_CLUSTER_6443 --protocol HTTPS--protocol-port 6443 API_OCP_CLUSTER

   Note

   To view the status of the load balancer, enter openstack loadbalancer list.

3. Create a pool that uses the round robin algorithm and has session persistence enabled:

   $ openstack loadbalancer pool create --name API_OCP_CLUSTER_pool_6443 --lb-algorithm ROUND_ROBIN --session-persistence type=<source_IP_address> --listener API_OCP_CLUSTER_6443 --protocol HTTPS

4. To ensure that control plane machines are available, create a health monitor:

   $ openstack loadbalancer healthmonitor create --delay 5 --max-retries 4 --timeout 10 --type TCP API_OCP_CLUSTER_pool_6443

5. Add the control plane machines as members of the load balancer pool:

   $ for SERVER in $(MASTER-0-IP MASTER-1-IP MASTER-2-IP)
   do
     openstack loadbalancer member create --address $SERVER  --protocol-port 6443 API_OCP_CLUSTER_pool_6443
   done

6. Optional: To reuse the cluster API floating IP address, unset it:

   $ openstack floating ip unset $API_FIP

7. Add either the unset API_FIP or a new address to the created load balancer VIP:

   $ openstack floating ip set  --port $(openstack loadbalancer show -c <vip_port_id> -f value API_OCP_CLUSTER) $API_FIP

Procedure

1. Configure the HAProxy Ingress Controller, so that you can enable access to the cluster from your load balancer on ports 6443, 22623, 443, and 80. Depending on your needs, you can specify the IP address of a single subnet or IP addresses from multiple subnets in your HAProxy configuration.

   Example HAProxy configuration with one listed subnet

   # ...
   listen my-cluster-api-6443
       bind 192.168.1.100:6443
       mode tcp
       balance roundrobin
     option httpchk
     http-check connect
     http-check send meth GET uri /readyz
     http-check expect status 200
       server my-cluster-master-2 192.168.1.101:6443 check inter 10s rise 2 fall 2
       server my-cluster-master-0 192.168.1.102:6443 check inter 10s rise 2 fall 2
       server my-cluster-master-1 192.168.1.103:6443 check inter 10s rise 2 fall 2
   
   listen my-cluster-machine-config-api-22623
       bind 192.168.1.100:22623
       mode tcp
       balance roundrobin
     option httpchk
     http-check connect
     http-check send meth GET uri /healthz
     http-check expect status 200
       server my-cluster-master-2 192.168.1.101:22623 check inter 10s rise 2 fall 2
       server my-cluster-master-0 192.168.1.102:22623 check inter 10s rise 2 fall 2
       server my-cluster-master-1 192.168.1.103:22623 check inter 10s rise 2 fall 2
   
   listen my-cluster-apps-443
       bind 192.168.1.100:443
       mode tcp
       balance roundrobin
     option httpchk
     http-check connect
     http-check send meth GET uri /healthz/ready
     http-check expect status 200
       server my-cluster-worker-0 192.168.1.111:443 check port 1936 inter 10s rise 2 fall 2
       server my-cluster-worker-1 192.168.1.112:443 check port 1936 inter 10s rise 2 fall 2
       server my-cluster-worker-2 192.168.1.113:443 check port 1936 inter 10s rise 2 fall 2
   
   listen my-cluster-apps-80
      bind 192.168.1.100:80
      mode tcp
      balance roundrobin
     option httpchk
     http-check connect
     http-check send meth GET uri /healthz/ready
     http-check expect status 200
       server my-cluster-worker-0 192.168.1.111:80 check port 1936 inter 10s rise 2 fall 2
       server my-cluster-worker-1 192.168.1.112:80 check port 1936 inter 10s rise 2 fall 2
       server my-cluster-worker-2 192.168.1.113:80 check port 1936 inter 10s rise 2 fall 2
   # ...

   Example HAProxy configuration with multiple listed subnets

   # ...
   listen api-server-6443
       bind *:6443
       mode tcp
         server master-00 192.168.83.89:6443 check inter 1s
         server master-01 192.168.84.90:6443 check inter 1s
         server master-02 192.168.85.99:6443 check inter 1s
         server bootstrap 192.168.80.89:6443 check inter 1s
   
   listen machine-config-server-22623
       bind *:22623
       mode tcp
         server master-00 192.168.83.89:22623 check inter 1s
         server master-01 192.168.84.90:22623 check inter 1s
         server master-02 192.168.85.99:22623 check inter 1s
         server bootstrap 192.168.80.89:22623 check inter 1s
   
   listen ingress-router-80
       bind *:80
       mode tcp
       balance source
         server worker-00 192.168.83.100:80 check inter 1s
         server worker-01 192.168.83.101:80 check inter 1s
   
   listen ingress-router-443
       bind *:443
       mode tcp
       balance source
         server worker-00 192.168.83.100:443 check inter 1s
         server worker-01 192.168.83.101:443 check inter 1s
   
   listen ironic-api-6385
       bind *:6385
       mode tcp
       balance source
         server master-00 192.168.83.89:6385 check inter 1s
         server master-01 192.168.84.90:6385 check inter 1s
         server master-02 192.168.85.99:6385 check inter 1s
         server bootstrap 192.168.80.89:6385 check inter 1s
   
   listen inspector-api-5050
       bind *:5050
       mode tcp
       balance source
         server master-00 192.168.83.89:5050 check inter 1s
         server master-01 192.168.84.90:5050 check inter 1s
         server master-02 192.168.85.99:5050 check inter 1s
         server bootstrap 192.168.80.89:5050 check inter 1s
   # ...

2. Use the curl CLI command to verify that the user-managed load balancer and its resources are operational:

   1. Verify that the cluster machine configuration API is accessible to the Kubernetes API server resource, by running the following command and observing the response:

      $ curl https://<loadbalancer_ip_address>:6443/version --insecure

      If the configuration is correct, you receive a JSON object in response:

      {
        "major": "1",
        "minor": "11+",
        "gitVersion": "v1.11.0+ad103ed",
        "gitCommit": "ad103ed",
        "gitTreeState": "clean",
        "buildDate": "2019-01-09T06:44:10Z",
        "goVersion": "go1.10.3",
        "compiler": "gc",
        "platform": "linux/amd64"
      }

   2. Verify that the cluster machine configuration API is accessible to the Machine config server resource, by running the following command and observing the output:

      $ curl -v https://<loadbalancer_ip_address>:22623/healthz --insecure

      If the configuration is correct, the output from the command shows the following response:

      HTTP/1.1 200 OK
      Content-Length: 0

   3. Verify that the controller is accessible to the Ingress Controller resource on port 80, by running the following command and observing the output:

      $ curl -I -L -H "Host: console-openshift-console.apps.<cluster_name>.<base_domain>" http://<load_balancer_front_end_IP_address>

      If the configuration is correct, the output from the command shows the following response:

      HTTP/1.1 302 Found
      content-length: 0
      location: https://console-openshift-console.apps.ocp4.private.opequon.net/
      cache-control: no-cache

   4. Verify that the controller is accessible to the Ingress Controller resource on port 443, by running the following command and observing the output:

      $ curl -I -L --insecure --resolve console-openshift-console.apps.<cluster_name>.<base_domain>:443:<Load Balancer Front End IP Address> https://console-openshift-console.apps.<cluster_name>.<base_domain>

      If the configuration is correct, the output from the command shows the following response:

      HTTP/1.1 200 OK
      referrer-policy: strict-origin-when-cross-origin
      set-cookie: csrf-token=UlYWOyQ62LWjw2h003xtYSKlh1a0Py2hhctw0WmV2YEdhJjFyQwWcGBsja261dGLgaYO0nxzVErhiXt6QepA7g==; Path=/; Secure; SameSite=Lax
      x-content-type-options: nosniff
      x-dns-prefetch-control: off
      x-frame-options: DENY
      x-xss-protection: 1; mode=block
      date: Wed, 04 Oct 2023 16:29:38 GMT
      content-type: text/html; charset=utf-8
      set-cookie: 1e2670d92730b515ce3a1bb65da45062=1bf5e9573c9a2760c964ed1659cc1673; path=/; HttpOnly; Secure; SameSite=None
      cache-control: private

3. Configure the DNS records for your cluster to target the front-end IP addresses of the user-managed load balancer. You must update records to your DNS server for the cluster API and applications over the load balancer.

   Examples of modified DNS records

   <load_balancer_ip_address>  A  api.<cluster_name>.<base_domain>
   A record pointing to Load Balancer Front End

   <load_balancer_ip_address>   A apps.<cluster_name>.<base_domain>
   A record pointing to Load Balancer Front End

   Important

   DNS propagation might take some time for each DNS record to become available. Ensure that each DNS record propagates before validating each record.

4. For your OpenShift Container Platform cluster to use the user-managed load balancer, you must specify the following configuration in your cluster’s install-config.yaml file:

   # ...
   platform:
     openstack:
       loadBalancer:
         type: UserManaged 1
         apiVIPs:
         - <api_ip> 2
         ingressVIPs:
         - <ingress_ip> 3
   # ...

   1

   Set UserManaged for the type parameter to specify a user-managed load balancer for your cluster. The parameter defaults to OpenShiftManagedDefault, which denotes the default internal load balancer. For services defined in an openshift-kni-infra namespace, a user-managed load balancer can deploy the coredns service to pods in your cluster but ignores keepalived and haproxy services.

   2

   Required parameter when you specify a user-managed load balancer. Specify the user-managed load balancer’s public IP address, so that the Kubernetes API can communicate with the user-managed load balancer.

   3

   Required parameter when you specify a user-managed load balancer. Specify the user-managed load balancer’s public IP address, so that the user-managed load balancer can manage ingress traffic for your cluster.

Verification

1. Use the curl CLI command to verify that the user-managed load balancer and DNS record configuration are operational:

   1. Verify that you can access the cluster API, by running the following command and observing the output:

      $ curl https://api.<cluster_name>.<base_domain>:6443/version --insecure

      If the configuration is correct, you receive a JSON object in response:

      {
        "major": "1",
        "minor": "11+",
        "gitVersion": "v1.11.0+ad103ed",
        "gitCommit": "ad103ed",
        "gitTreeState": "clean",
        "buildDate": "2019-01-09T06:44:10Z",
        "goVersion": "go1.10.3",
        "compiler": "gc",
        "platform": "linux/amd64"
        }

   2. Verify that you can access the cluster machine configuration, by running the following command and observing the output:

      $ curl -v https://api.<cluster_name>.<base_domain>:22623/healthz --insecure

      If the configuration is correct, the output from the command shows the following response:

      HTTP/1.1 200 OK
      Content-Length: 0

   3. Verify that you can access each cluster application on port, by running the following command and observing the output:

      $ curl http://console-openshift-console.apps.<cluster_name>.<base_domain> -I -L --insecure

      If the configuration is correct, the output from the command shows the following response:

      HTTP/1.1 302 Found
      content-length: 0
      location: https://console-openshift-console.apps.<cluster-name>.<base domain>/
      cache-control: no-cacheHTTP/1.1 200 OK
      referrer-policy: strict-origin-when-cross-origin
      set-cookie: csrf-token=39HoZgztDnzjJkq/JuLJMeoKNXlfiVv2YgZc09c3TBOBU4NI6kDXaJH1LdicNhN1UsQWzon4Dor9GWGfopaTEQ==; Path=/; Secure
      x-content-type-options: nosniff
      x-dns-prefetch-control: off
      x-frame-options: DENY
      x-xss-protection: 1; mode=block
      date: Tue, 17 Nov 2020 08:42:10 GMT
      content-type: text/html; charset=utf-8
      set-cookie: 1e2670d92730b515ce3a1bb65da45062=9b714eb87e93cf34853e87a92d6894be; path=/; HttpOnly; Secure; SameSite=None
      cache-control: private

   4. Verify that you can access each cluster application on port 443, by running the following command and observing the output:

      $ curl https://console-openshift-console.apps.<cluster_name>.<base_domain> -I -L --insecure

      If the configuration is correct, the output from the command shows the following response:

      HTTP/1.1 200 OK
      referrer-policy: strict-origin-when-cross-origin
      set-cookie: csrf-token=UlYWOyQ62LWjw2h003xtYSKlh1a0Py2hhctw0WmV2YEdhJjFyQwWcGBsja261dGLgaYO0nxzVErhiXt6QepA7g==; Path=/; Secure; SameSite=Lax
      x-content-type-options: nosniff
      x-dns-prefetch-control: off
      x-frame-options: DENY
      x-xss-protection: 1; mode=block
      date: Wed, 04 Oct 2023 16:29:38 GMT
      content-type: text/html; charset=utf-8
      set-cookie: 1e2670d92730b515ce3a1bb65da45062=1bf5e9573c9a2760c964ed1659cc1673; path=/; HttpOnly; Secure; SameSite=None
      cache-control: private