2 files changed, 24 insertions, 6 deletions
diff --git a/pkg/specgen/generate/container.go b/pkg/specgen/generate/container.go
index 2ee8f2441..c7e62d185 100644
--- a/pkg/specgen/generate/container.go
+++ b/pkg/specgen/generate/container.go
@@ -257,7 +257,19 @@ func CompleteSpec(ctx context.Context, r *libpod.Runtime, s *specgen.SpecGenerat
 		}
 	}
 
-	return verifyContainerResources(s)
+	warnings, err := verifyContainerResources(s)
+	if err != nil {
+		return warnings, err
+	}
+
+	// Warn on net=host/container/pod/none and port mappings.
+	if (s.NetNS.NSMode == specgen.Host || s.NetNS.NSMode == specgen.FromContainer ||
+		s.NetNS.NSMode == specgen.FromPod || s.NetNS.NSMode == specgen.NoNetwork) &&
+		len(s.PortMappings) > 0 {
+		warnings = append(warnings, "Port mappings have been discarded as one of the Host, Container, Pod, and None network modes are in use")
+	}
+
+	return warnings, nil
 }
 
 // finishThrottleDevices takes the temporary representation of the throttle
diff --git a/pkg/specgen/namespaces.go b/pkg/specgen/namespaces.go
index 11108a5c1..9f0dd80de 100644
--- a/pkg/specgen/namespaces.go
+++ b/pkg/specgen/namespaces.go
@@ -27,19 +27,25 @@ const (
 	// Private indicates the namespace is private
 	Private NamespaceMode = "private"
 	// NoNetwork indicates no network namespace should
-	// be joined.  loopback should still exists
+	// be joined.  loopback should still exists.
+	// Only used with the network namespace, invalid otherwise.
 	NoNetwork NamespaceMode = "none"
 	// Bridge indicates that a CNI network stack
-	// should be used
+	// should be used.
+	// Only used with the network namespace, invalid otherwise.
 	Bridge NamespaceMode = "bridge"
 	// Slirp indicates that a slirp4netns network stack should
-	// be used
+	// be used.
+	// Only used with the network namespace, invalid otherwise.
 	Slirp NamespaceMode = "slirp4netns"
 	// KeepId indicates a user namespace to keep the owner uid inside
-	// of the namespace itself
+	// of the namespace itself.
+	// Only used with the user namespace, invalid otherwise.
 	KeepID NamespaceMode = "keep-id"
-	// KeepId indicates to automatically create a user namespace
+	// Auto indicates to automatically create a user namespace.
+	// Only used with the user namespace, invalid otherwise.
 	Auto NamespaceMode = "auto"
+
 	// DefaultKernelNamespaces is a comma-separated list of default kernel
 	// namespaces.
 	DefaultKernelNamespaces = "cgroup,ipc,net,uts"