[mdadm] Handle inactive arrays correctly

Currently we don't handle inactive arrays correctly, this will do so better.
Tests included.

Signed-off-by: Phil Dibowitz <phil@ipom.com>

2 files changed, 16 insertions, 2 deletions

diff --git a/lib/ohai/plugins/linux/mdadm.rb b/lib/ohai/plugins/linux/mdadm.rb
index 85290908..4def6c50 100644
--- a/lib/ohai/plugins/linux/mdadm.rb
+++ b/lib/ohai/plugins/linux/mdadm.rb
@@ -60,9 +60,12 @@ Ohai.plugin(:Mdadm) do
           device = Regexp.last_match[1]
           pieces = line.split(/\s+/)
           # there are variable numbers of fields until you hit the raid level
-          # everything after that is members
-          members = pieces.drop_while { |x| !x.start_with?("raid") }
+          # everything after that is members...
+          # unless the array is inactive, in which case you don't get a raid
+          # level.
+          members = pieces.drop_while { |x| !x.start_with?("raid", "inactive") }
           # drop the 'raid' too
+
           members.shift unless members.empty?
           devices[device] = members.map { |s| s.match(/(.+)\[\d\]/)[1] }
         end
diff --git a/spec/unit/plugins/linux/mdadm_spec.rb b/spec/unit/plugins/linux/mdadm_spec.rb
index f437e0d8..9b6f9e0c 100644
--- a/spec/unit/plugins/linux/mdadm_spec.rb
+++ b/spec/unit/plugins/linux/mdadm_spec.rb
@@ -119,6 +119,17 @@ MD
         %w{sdc sdd sde sdf sdg sdh}
       )
     end
+
+    it "should accurately report inactive arrays" do
+      new_mdstat = double("/proc/mdstat_inactive")
+      allow(new_mdstat).to receive(:each).
+        and_yield("Personalities :").
+        and_yield("md0 : inactive nvme2n1p3[2](S)")
+      allow(File).to receive(:open).with("/proc/mdstat").and_return(new_mdstat)
+
+      @plugin.run
+      expect(@plugin[:mdadm][:md0][:members].sort).to eq(%w{nvme2n1p3})
+    end
   end
 
 end