Merge pull request #787 from tas50/gce_fix

Remove ec2metadata CLI as a EC2 detection method

2 files changed, 10 insertions, 40 deletions

diff --git a/lib/ohai/plugins/ec2.rb b/lib/ohai/plugins/ec2.rb
index 1f383035..a9c7eff7 100644
--- a/lib/ohai/plugins/ec2.rb
+++ b/lib/ohai/plugins/ec2.rb
@@ -17,6 +17,11 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+# How we detect EC2 from easiest to hardest & least reliable
+# 1. Ohai ec2 hint exists. This always works
+# 2. DMI data mentions amazon. This catches HVM instances in a VPC
+# 3. Has a xen MAC + can connect to metadata. This catches paravirt instances not in a VPC
+
 require "ohai/mixin/ec2_metadata"
 require "base64"
 
@@ -28,18 +33,8 @@ Ohai.plugin(:EC2) do
   depends "network/interfaces"
   depends "dmi"
 
-  # look for ec2metadata which is included on paravirt / hvm AMIs
-  def has_ec2metadata_bin?
-    if File.exist?("/usr/bin/ec2metadata")
-      Ohai::Log.debug("ec2 plugin: has_ec2metadata_bin? == true")
-      true
-    else
-      Ohai::Log.debug("ec2 plugin: has_ec2metadata_bin? == false")
-      false
-    end
-  end
-
-  # look for arp address that non-VPC hosts will have
+  # look for xen arp address
+  # this gets us detection of paravirt instances that are NOT within a VPC
   def has_xen_mac?
     network[:interfaces].values.each do |iface|
       unless iface[:arp].nil?
@@ -60,7 +55,7 @@ EOM
   end
 
   # look for amazon string in dmi bios data
-  # this only works on hvm instances as paravirt instances have no dmi data
+  # this gets us detection of HVM instances that are within a VPC
   def has_ec2_dmi?
     begin
       # detect a version of '4.2.amazon'
@@ -74,16 +69,11 @@ EOM
     end
   end
 
-  # rackspace systems look like ec2 so instead of timing out dig a bit deeper
-  def looks_like_rackspace?
-    return true if File.exist?("/usr/bin/rackspace-monitoring-agent")
-  end
-
   def looks_like_ec2?
     return true if hint?("ec2")
 
     # Even if it looks like EC2 try to connect first
-    if has_ec2_dmi? || has_xen_mac? || (has_ec2metadata_bin? && !looks_like_rackspace?)
+    if has_ec2_dmi? || has_xen_mac?
       return true if can_metadata_connect?(Ohai::Mixin::Ec2Metadata::EC2_METADATA_ADDR, 80)
     end
   end
diff --git a/spec/unit/plugins/ec2_spec.rb b/spec/unit/plugins/ec2_spec.rb
index bddd887b..1098b5fa 100644
--- a/spec/unit/plugins/ec2_spec.rb
+++ b/spec/unit/plugins/ec2_spec.rb
@@ -27,8 +27,6 @@ describe Ohai::System, "plugin ec2" do
     @plugin[:network] = { :interfaces => { :eth0 => {} } }
     allow(File).to receive(:exist?).with("/etc/chef/ohai/hints/ec2.json").and_return(false)
     allow(File).to receive(:exist?).with('C:\chef\ohai\hints/ec2.json').and_return(false)
-    allow(File).to receive(:exist?).with("/usr/bin/ec2metadata").and_return(false)
-    allow(File).to receive(:exist?).with("/usr/bin/rackspace-monitoring-agent").and_return(false)
   end
 
   shared_examples_for "!ec2" do
@@ -256,7 +254,7 @@ describe Ohai::System, "plugin ec2" do
     end
   end # shared examples for ec2
 
-  describe "without dmi or ec2metadata binary, with xen mac, and metadata address connected" do
+  describe "without dmi data, kernel organization, with xen mac, and metadata address connected" do
     before(:each) do
       allow(IO).to receive(:select).and_return([[], [1], []])
       @plugin[:network][:interfaces][:eth0][:arp] = { "169.254.1.0" => "fe:ff:ff:ff:ff:ff" }
@@ -270,14 +268,6 @@ describe Ohai::System, "plugin ec2" do
     end
   end
 
-  describe "with ec2metadata binary" do
-    it_should_behave_like "ec2"
-
-    before(:each) do
-      allow(File).to receive(:exist?).with("/usr/bin/ec2metadata").and_return(true)
-    end
-  end
-
   describe "with ec2 dmi data" do
     it_should_behave_like "ec2"
 
@@ -311,22 +301,12 @@ describe Ohai::System, "plugin ec2" do
     end
   end
 
-  describe "with ec2metadata, but with rackspace-monitoring-agent" do
-    it_should_behave_like "!ec2"
-
-    before(:each) do
-      allow(File).to receive(:exist?).with("/usr/bin/ec2metadata").and_return(true)
-      allow(File).to receive(:exist?).with("/usr/bin/rackspace-monitoring-agent").and_return(true)
-    end
-  end
-
   describe "without any hints that it is an ec2 system" do
     it_should_behave_like "!ec2"
 
     before(:each) do
       allow(File).to receive(:exist?).with("/etc/chef/ohai/hints/ec2.json").and_return(false)
       allow(File).to receive(:exist?).with('C:\chef\ohai\hints/ec2.json').and_return(false)
-      allow(File).to receive(:exist?).with("/usr/bin/ec2metadata").and_return(false)
       @plugin[:dmi] = nil
       @plugin[:network][:interfaces][:eth0][:arp] = { "169.254.1.0" => "00:50:56:c0:00:08" }
     end