It looks like you are missing a / in the src= part of your synchronize action, here:
- name: Synchronizacja
synchronize: src=etc/corosync/authkey dest=/etc/corosync/authkey
delegate_to: 192.168.10.186
instead try
- name: Synchronizacja
synchronize: src=/etc/corosync/authkey dest=/etc/corosync/authkey
delegate_to: 192.168.10.186
You might find it easier to use 'yaml style' module parameters like this
- name: Synchronizacja
synchronize:
src: /etc/corosync/authkey
dest: /etc/corosync/authkey
delegate_to: 192.168.10.186
Personally I find this easier to read than the key=value key=value style.
Hope this helps,
Jon