Add ping_access_ip; allows to disable ping test (#7020)

In some environments, it might not be possible to ping the IP address
of the nodes, e.g., because ICMP echo is blocked.

This commit allows kubespray to be configured to disable the ping
check, while performing all other checks.

inventory/sample/group_vars/all/all.yml

@@ -109,3 +109,6 @@ no_proxy_exclude_workers: false
 # rh_subscription_usage: "Development"
 # rh_subscription_role: "Red Hat Enterprise Server"
 # rh_subscription_sla: "Self-Support"
+
+## Check if access_ip responds to ping. Set false if your firewall blocks ICMP.
+# ping_access_ip: true

roles/kubernetes/preinstall/defaults/main.yml

@@ -56,3 +56,6 @@ yum_repo_dir: /etc/yum.repos.d
 
 # number of times package install task should be retried
 pkg_install_retries: 4
+
+# Check if access_ip responds to ping. Set false if your firewall blocks ICMP.
+ping_access_ip: true

roles/kubernetes/preinstall/tasks/0020-verify-settings.yml

@@ -114,6 +114,7 @@
   when:
     - access_ip is defined
     - not ignore_assert_errors
+    - ping_access_ip
 
 - name: Stop if RBAC is not enabled when dashboard is enabled
   assert: