Roles can fail if the skip_install variable is set to true for a subset of the hosts the role is being used on

[alkinks]

If, for a group of hosts you have _skip_install set to true for a subset of those hosts & the playbook runs on one of this subset first, the run_once means the task to get the binary checksums is skipped, and subsequent tasks will fail.

Running molecule converge on the current chrony_exporter role, with chrony_exporter_skip_install=true I get this output (truncated).

I'd get the same issue for all hosts if chrony_exporter_skip_install=true was just set for the almalinux-8 host as that's the first host to be tried.

TASK [chrony_exporter : Discover latest version] *******************************
skipping: [almalinux-8] => {"changed": false, "skip_reason": "Conditional result was False"}

TASK [chrony_exporter : Get checksum list from github] *************************
skipping: [almalinux-8] => {"changed": false, "skip_reason": "Conditional result was False"}

TASK [chrony_exporter : Get checksum for amd64] ********************************
skipping: [almalinux-8] => {"changed": false, "skip_reason": "Conditional result was False"}
fatal: [almalinux-9]: FAILED! => {"msg": "'__chrony_exporter_checksums' is undefined"}
fatal: [centos-7]: FAILED! => {"msg": "'__chrony_exporter_checksums' is undefined"}
fatal: [centos-stream-8]: FAILED! => {"msg": "'__chrony_exporter_checksums' is undefined"}
fatal: [debian-10]: FAILED! => {"msg": "'__chrony_exporter_checksums' is undefined"}
fatal: [debian-11]: FAILED! => {"msg": "'__chrony_exporter_checksums' is undefined"}
fatal: [fedora-37]: FAILED! => {"msg": "'__chrony_exporter_checksums' is undefined"}
fatal: [fedora-38]: FAILED! => {"msg": "'__chrony_exporter_checksums' is undefined"}
fatal: [ubuntu-20.04]: FAILED! => {"msg": "'__chrony_exporter_checksums' is undefined"}
fatal: [ubuntu-22.04]: FAILED! => {"msg": "'__chrony_exporter_checksums' is undefined"}

NO MORE HOSTS LEFT *************************************************************

PLAY RECAP *********************************************************************
almalinux-8                : ok=8    changed=0    unreachable=0    failed=0    skipped=9    rescued=0    ignored=0
almalinux-9                : ok=8    changed=0    unreachable=0    failed=1    skipped=6    rescued=0    ignored=0
centos-7                   : ok=8    changed=0    unreachable=0    failed=1    skipped=6    rescued=0    ignored=0
centos-stream-8            : ok=8    changed=0    unreachable=0    failed=1    skipped=6    rescued=0    ignored=0
centos-stream-9            : ok=8    changed=0    unreachable=0    failed=1    skipped=6    rescued=0    ignored=0
debian-10                  : ok=9    changed=0    unreachable=0    failed=1    skipped=5    rescued=0    ignored=0
debian-11                  : ok=9    changed=0    unreachable=0    failed=1    skipped=5    rescued=0    ignored=0
fedora-37                  : ok=8    changed=0    unreachable=0    failed=1    skipped=6    rescued=0    ignored=0
fedora-38                  : ok=8    changed=0    unreachable=0    failed=1    skipped=6    rescued=0    ignored=0
ubuntu-20.04               : ok=9    changed=0    unreachable=0    failed=1    skipped=5    rescued=0    ignored=0
ubuntu-22.04               : ok=9    changed=0    unreachable=0    failed=1    skipped=5    rescued=0    ignored=0

The download of the checksum needs to happen on at least one not skipped host.