symLinkEngineBinary doesn't work with custom docker engine from url

[stffabi]

RancherOS Version: (ros os version)

v1.5.4-rc1

Where are you running RancherOS? (docker-machine, AWS, GCE, baremetal, etc.)

vSphere

symLinkEngineBinary can't detect the docker version if a custom docker engine is used as documented here. In such a case symLinkEngineBinary receives the URL to the engine service file and fails to determine the docker version. Therefore if the custom docker engine is newer or equal to 18.09.0 rancher tries to create the wrong symlinks (e.g. for runc). As a result RancherOS doesn't boot anymore.

[niusmallnan]

I can reproduce this issue with this cloud-config.

#cloud-config 
rancher:
  docker:
    engine: https://raw.githubusercontent.com/rancher/os-services/master/d/docker-18.09.7.yml

[stffabi]

Successfully tested on v1.5.4-rc2

[stffabi]

Thanks for the fix

[kingsd041]

Fixed on v1.5.4-rc2, close this issue.