Use timeout to kill vrnetlab readiness check SSH sessions (#1734)

The SSH client used to check vrnetlab readiness can be stuck for
an awfully long when the VM is in just the right phase of getting
ready. This change uses the 'timeout' command (when available) to
kill the check after 5 seconds, allowing the Ansible retry mechanism
to work as expected.

netsim/ansible/tasks/readiness-check/vm-clab-ssh-check.yml

@@ -10,11 +10,18 @@
   run_once: True
   any_errors_fatal: True
 
+- name: Check for 'timeout' command
+  local_action:
+    module: shell
+    cmd: which timeout || echo "FAILED"
+  changed_when: False
+  register: have_timeout
+
 - name: Execute local ssh command to check {{ netlab_device_type|default(inventory_hostname) }} readiness
   local_action:
     module: shell
     cmd: |
-      sshpass -p '{{ ansible_ssh_pass }}' \
+      {{ 'timeout -k 3s 5s' if "FAILED" not in have_timeout.stdout else '' }} sshpass -p '{{ ansible_ssh_pass }}' \
       ssh -o StrictHostKeyChecking=no {{ netlab_ssh_args|default('') }} \
           -o UserKnownHostsFile=/dev/null {{ ansible_user }}@{{ ansible_host }} \
           '{{ netlab_check_command | default("show version") }}'

netsim/devices/vjunos-router.yml

@@ -24,7 +24,7 @@ clab:
   group_vars:
     ansible_user: admin
     ansible_ssh_pass: admin@123
-    netlab_check_retries: 40
+    netlab_check_retries: 60
     netlab_check_delay: 10
 
 graphite.icon: router