[MESOS-7348] Network isolator crashes agent on startup when network interface cannot be found

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 1.1.0
• Fix Version/s: 1.3.0
• Component/s: containerization, network
• Assignee: Dmitry Zhuk
• Reporter: Dmitry Zhuk
• Shepherd: Jie Yu
• Created: 05/Apr/17 13:24
• Updated: 26/Apr/17 16:53
• Resolved: 06/Apr/17 23:35

Description

When there's no public network interface, network isolator does not properly handle None and crashes on trying to obtain error message from Result:

  } else if (!eth0.isSome()){
    // eth0 is not specified in the flag and we did not get a valid
    // eth0 from the library.
    return Error(
        "Network Isolator failed to find a public interface: " + eth0.error());
  }

There's also similar issue in code handling loopback interface.