How to ignore the connection error in play - ansible

Question

I want to continue my playbook to do some other tasks when some hosts are unreachable. However, the ignore_errors seems doesn't work. The debug msg is not printed.
ansible version is 2.5.4. Is there a way to do this in this version?
- name: check accessibility
hosts: myhosts
tasks:
- ping:
ignore_errors: yes
- fail:
msg: "Host {{ansible_hostname}} is not accessible"
when: False

Answer 1

An option would be to ping each 'inventory_hostname' in the block and end the play if the ping fails.
- hosts: myhosts
gather_facts: no
tasks:
- block:
- delegate_to: localhost
command: ping -c1 "{{ inventory_hostname }}"
rescue:
- fail:
msg: "{{ inventory_hostname }} not accessible. End of play."
- debug:
msg: "Host {{ inventory_hostname }} continue play."
- setup:
Notes:
Set 'gather_facts: no', because we are not sure all hosts are available
Use 'inventory_hostname', because of 'gather_facts: no'
use 'setup' module after the 'block' if necessary
Running the playbook with available hosts: test_01, test_02, test_03 and unavailable host test_99 gives (abridged):
TASK [fail]
fatal: [test_99]: FAILED! => {"changed": false, "msg": "test_99 not accessible. End of play."}
TASK [debug]
ok: [test_03] => {
"msg": "Host test_03 continue play."
}
ok: [test_01] => {
"msg": "Host test_01 continue play."
}
ok: [test_02] => {
"msg": "Host test_02 continue play."
}
TASK [setup]
ok: [test_03]
ok: [test_01]
ok: [test_02]
PLAY RECAP
test_01 : ok=3 changed=1 unreachable=0 failed=0
test_02 : ok=3 changed=1 unreachable=0 failed=0
test_03 : ok=3 changed=1 unreachable=0 failed=0
test_99 : ok=0 changed=0 unreachable=0 failed=2