Better debug logging

Gracefully fail in virtual box
Include plugin name in more logs
Be consistent in the log output format
Help figure out how Virtualization systems were detected with logging

Signed-off-by: Tim Smith <tsmith@chef.io>

19 files changed, 127 insertions, 102 deletions

diff --git a/lib/ohai/plugins/azure.rb b/lib/ohai/plugins/azure.rb
index 8bc29964..8d984083 100644
--- a/lib/ohai/plugins/azure.rb
+++ b/lib/ohai/plugins/azure.rb
@@ -24,14 +24,14 @@ Ohai.plugin(:Azure) do
     # project for details
     azure_metadata_from_hints = hint?("azure")
     if azure_metadata_from_hints
-      Ohai::Log.debug("azure plugin: azure_metadata_from_hints is present.")
+      Ohai::Log.debug("Plugin Azure: azure_metadata_from_hints is present.")
       azure Mash.new
       azure_metadata_from_hints.each { |k, v| azure[k] = v }
     elsif has_waagent? || has_dhcp_option_245?
-      Ohai::Log.debug("azure plugin: No hints present, but system appears to be on azure.")
+      Ohai::Log.debug("Plugin Azure: No hints present, but system appears to be on azure.")
       azure Mash.new
     else
-      Ohai::Log.debug("azure plugin: No hints present for azure and doesn't appear to be azure.")
+      Ohai::Log.debug("Plugin Azure: No hints present for azure and doesn't appear to be azure.")
       false
     end
   end
@@ -40,7 +40,7 @@ Ohai.plugin(:Azure) do
   # http://blog.mszcool.com/index.php/2015/04/detecting-if-a-virtual-machine-runs-in-microsoft-azure-linux-windows-to-protect-your-software-when-distributed-via-the-azure-marketplace/
   def has_waagent?
     if File.exist?("/usr/sbin/waagent") || Dir.exist?('C:\WindowsAzure')
-      Ohai::Log.debug("azure plugin: Found waagent used by MS Azure.")
+      Ohai::Log.debug("Plugin Azure: Found waagent used by MS Azure.")
       return true
     end
   end
@@ -50,7 +50,7 @@ Ohai.plugin(:Azure) do
     if File.exist?("/var/lib/dhcp/dhclient.eth0.leases")
       File.open("/var/lib/dhcp/dhclient.eth0.leases").each do |line|
         if line =~ /unknown-245/
-          Ohai::Log.debug("azure plugin: Found unknown-245 DHCP option used by MS Azure.")
+          Ohai::Log.debug("Plugin Azure: Found unknown-245 DHCP option used by MS Azure.")
           has_245 = true
           break
         end
diff --git a/lib/ohai/plugins/c.rb b/lib/ohai/plugins/c.rb
index e5107cdc..3dee1492 100644
--- a/lib/ohai/plugins/c.rb
+++ b/lib/ohai/plugins/c.rb
@@ -28,10 +28,10 @@ Ohai.plugin(:C) do
     if so.exitstatus == 0
       yield(so)
     else
-      Ohai::Log.debug("Plugin C '#{cmd}' failed. Skipping data.")
+      Ohai::Log.debug("Plugin C: '#{cmd}' failed. Skipping data.")
     end
   rescue Ohai::Exceptions::Exec
-    Ohai::Log.debug("Plugin C '#{cmd}' binary could not be found. Skipping data.")
+    Ohai::Log.debug("Plugin C: '#{cmd}' binary could not be found. Skipping data.")
   end
 
   collect_data do
diff --git a/lib/ohai/plugins/dmi.rb b/lib/ohai/plugins/dmi.rb
index bcda1c4a..6acf7feb 100644
--- a/lib/ohai/plugins/dmi.rb
+++ b/lib/ohai/plugins/dmi.rb
@@ -92,14 +92,14 @@ Ohai.plugin(:DMI) do
 
       elsif type = type_line.match(line)
         if dmi_record == nil
-          Ohai::Log.debug("unexpected data line found before header; discarding:\n#{line}")
+          Ohai::Log.debug("Plugin DMI: unexpected data line found before header; discarding:\n#{line}")
           next
         end
         dmi[dmi_record[:type]][:all_records][dmi_record[:position]][:application_identifier] = type[1]
 
       elsif data = data_line.match(line)
         if dmi_record == nil
-          Ohai::Log.debug("unexpected data line found before header; discarding:\n#{line}")
+          Ohai::Log.debug("Plugin DMI: unexpected data line found before header; discarding:\n#{line}")
           next
         end
         dmi[dmi_record[:type]][:all_records][dmi_record[:position]][data[1]] = data[2]
@@ -107,11 +107,11 @@ Ohai.plugin(:DMI) do
 
       elsif extended_data = extended_data_line.match(line)
         if dmi_record == nil
-          Ohai::Log.debug("unexpected extended data line found before header; discarding:\n#{line}")
+          Ohai::Log.debug("Plugin DMI: unexpected extended data line found before header; discarding:\n#{line}")
           next
         end
         if field == nil
-          Ohai::Log.debug("unexpected extended data line found outside data section; discarding:\n#{line}")
+          Ohai::Log.debug("Plugin DMI: unexpected extended data line found outside data section; discarding:\n#{line}")
           next
         end
         # overwrite "raw" value with a new Mash
@@ -119,7 +119,7 @@ Ohai.plugin(:DMI) do
         dmi[dmi_record[:type]][:all_records][dmi_record[:position]][field][extended_data[1]] = nil
 
       else
-        Ohai::Log.debug("unrecognized output line; discarding:\n#{line}")
+        Ohai::Log.debug("Plugin DMI: unrecognized output line; discarding:\n#{line}")
 
       end
     end
diff --git a/lib/ohai/plugins/groovy.rb b/lib/ohai/plugins/groovy.rb
index 7edbb67c..431a9dab 100644
--- a/lib/ohai/plugins/groovy.rb
+++ b/lib/ohai/plugins/groovy.rb
@@ -32,7 +32,7 @@ Ohai.plugin(:Groovy) do
         languages[:groovy] = groovy
       end
     rescue Ohai::Exceptions::Exec
-      Ohai::Log.debug('Groovy plugin: Could not shell_out "groovy -v". Skipping plugin')
+      Ohai::Log.debug('Plugin Groovy: Could not shell_out "groovy -v". Skipping plugin')
     end
   end
 end
diff --git a/lib/ohai/plugins/haskell.rb b/lib/ohai/plugins/haskell.rb
index d3070e04..07132581 100644
--- a/lib/ohai/plugins/haskell.rb
+++ b/lib/ohai/plugins/haskell.rb
@@ -39,7 +39,7 @@ Ohai.plugin(:Haskell) do
         haskell[:ghc][:description] = so.stdout.chomp
       end
     rescue Ohai::Exceptions::Exec
-      Ohai::Log.debug('Haskell plugin: Could not shell_out "ghc --version". Skipping data')
+      Ohai::Log.debug('Plugin Haskell: Could not shell_out "ghc --version". Skipping data')
     end
 
     # Check for ghci
@@ -54,7 +54,7 @@ Ohai.plugin(:Haskell) do
         haskell[:ghci][:description] = so.stdout.chomp
       end
     rescue Ohai::Exceptions::Exec
-      Ohai::Log.debug('Haskell plugin: Could not shell_out "ghci --version". Skipping data')
+      Ohai::Log.debug('Plugin Haskell: Could not shell_out "ghci --version". Skipping data')
     end
 
     # Check for cabal
@@ -70,7 +70,7 @@ Ohai.plugin(:Haskell) do
         haskell[:cabal][:description] = so.stdout.split("\n")[0].chomp
       end
     rescue Ohai::Exceptions::Exec
-      Ohai::Log.debug('Haskell plugin: Could not shell_out "cabal --version". Skipping data')
+      Ohai::Log.debug('Plugin Haskell: Could not shell_out "cabal --version". Skipping data')
     end
 
     # Check for stack
@@ -87,7 +87,7 @@ Ohai.plugin(:Haskell) do
         haskell[:stack][:description] = so.stdout.chomp
       end
     rescue Ohai::Exceptions::Exec
-      Ohai::Log.debug('Haskell plugin: Could not shell_out "stack --version". Skipping data')
+      Ohai::Log.debug('Plugin Haskell: Could not shell_out "stack --version". Skipping data')
     end
 
     languages[:haskell] = haskell unless haskell.empty?
diff --git a/lib/ohai/plugins/hostname.rb b/lib/ohai/plugins/hostname.rb
index 0f1b2c22..32d95fb3 100644
--- a/lib/ohai/plugins/hostname.rb
+++ b/lib/ohai/plugins/hostname.rb
@@ -120,19 +120,19 @@ Ohai.plugin(:Hostname) do
       # Sometimes... very rarely, but sometimes, 'hostname --fqdn' falsely
       # returns a blank string. WTF.
       if ourfqdn.nil? || ourfqdn.empty?
-        Ohai::Log.debug("hostname returned an empty string, retrying once.")
+        Ohai::Log.debug("Plugin Hostname: hostname returned an empty string, retrying once.")
         ourfqdn = resolve_fqdn
       end
 
       if ourfqdn.nil? || ourfqdn.empty?
-        Ohai::Log.debug("hostname returned an empty string twice and will" +
+        Ohai::Log.debug("Plugin Hostname: hostname returned an empty string twice and will" +
                         "not be set.")
       else
         fqdn ourfqdn
       end
     rescue
       Ohai::Log.debug(
-        "hostname returned an error, probably no domain set")
+        "Plugin Hostname: hostname returned an error, probably no domain set")
     end
     domain collect_domain
   end
@@ -152,20 +152,20 @@ Ohai.plugin(:Hostname) do
       # Sometimes... very rarely, but sometimes, 'hostname --fqdn' falsely
       # returns a blank string. WTF.
       if ourfqdn.nil? || ourfqdn.empty?
-        Ohai::Log.debug("hostname --fqdn returned an empty string, retrying " +
+        Ohai::Log.debug("Plugin Hostname: hostname --fqdn returned an empty string, retrying " +
                         "once.")
         ourfqdn = from_cmd("hostname --fqdn")
       end
 
       if ourfqdn.nil? || ourfqdn.empty?
-        Ohai::Log.debug("hostname --fqdn returned an empty string twice and " +
+        Ohai::Log.debug("Plugin Hostname: hostname --fqdn returned an empty string twice and " +
                         "will not be set.")
       else
         fqdn ourfqdn
       end
     rescue
       Ohai::Log.debug(
-        "hostname --fqdn returned an error, probably no domain set")
+        "Plugin Hostname: hostname --fqdn returned an error, probably no domain set")
     end
     domain collect_domain
   end
diff --git a/lib/ohai/plugins/ip_scopes.rb b/lib/ohai/plugins/ip_scopes.rb
index e9367762..5ef5474e 100644
--- a/lib/ohai/plugins/ip_scopes.rb
+++ b/lib/ohai/plugins/ip_scopes.rb
@@ -43,7 +43,7 @@ Ohai.plugin(:IpScopes) do
 
     rescue LoadError => e
       # our favourite gem is not installed. Boohoo.
-      Ohai::Log.debug("Plugin ip_scopes: cannot load gem, plugin disabled: #{e}")
+      Ohai::Log.debug("Plugin IpScopes: cannot load gem, plugin disabled: #{e}")
     end
   end
 
diff --git a/lib/ohai/plugins/linux/network.rb b/lib/ohai/plugins/linux/network.rb
index 98c95245..5d9c2952 100644
--- a/lib/ohai/plugins/linux/network.rb
+++ b/lib/ohai/plugins/linux/network.rb
@@ -80,7 +80,7 @@ Ohai.plugin(:Network) do
     so = shell_out("ip -o -f #{family[:name]} route show table #{default_route_table}")
     so.stdout.lines do |line|
       line.strip!
-      Ohai::Log.debug("Parsing #{line}")
+      Ohai::Log.debug("Plugin Network: Parsing #{line}")
       if line =~ /\\/
         parts = line.split('\\')
         route_dest = parts.shift.strip
@@ -95,13 +95,13 @@ Ohai.plugin(:Network) do
         if route_ending =~ /\bdev\s+([^\s]+)\b/
           route_int = $1
         else
-          Ohai::Log.debug("Skipping route entry without a device: '#{line}'")
+          Ohai::Log.debug("Plugin Network: Skipping route entry without a device: '#{line}'")
           next
         end
         route_int = "venet0:0" if is_openvz? && !is_openvz_host? && route_int == "venet0" && iface["venet0:0"]
 
         unless iface[route_int]
-          Ohai::Log.debug("Skipping previously unseen interface from 'ip route show': #{route_int}")
+          Ohai::Log.debug("Plugin Network: Skipping previously unseen interface from 'ip route show': #{route_int}")
           next
         end
 
@@ -118,7 +118,7 @@ Ohai.plugin(:Network) do
           addr = iface[route_int][:addresses]
           unless addr.nil? || addr.has_key?(route_entry[:src]) ||
               addr.values.all? { |a| a["family"] != family[:name] }
-            Ohai::Log.debug("Skipping route entry whose src does not match the interface IP")
+            Ohai::Log.debug("Plugin Network: Skipping route entry whose src does not match the interface IP")
             next
           end
         end
@@ -156,7 +156,7 @@ Ohai.plugin(:Network) do
       so = shell_out("#{ethtool_binary} #{tmp_int}")
       so.stdout.lines do |line|
         line.chomp!
-        Ohai::Log.debug("Parsing ethtool output: #{line}")
+        Ohai::Log.debug("Plugin Network: Parsing ethtool output: #{line}")
         line.lstrip!
         k, v = line.split(": ")
         next unless keys.include? k
@@ -177,7 +177,7 @@ Ohai.plugin(:Network) do
     iface.each_key do |tmp_int|
       next unless iface[tmp_int][:encapsulation] == "Ethernet"
       so = shell_out("#{ethtool_binary} -g #{tmp_int}")
-      Ohai::Log.debug("Parsing ethtool output: #{so.stdout}")
+      Ohai::Log.debug("Plugin Network: Parsing ethtool output: #{so.stdout}")
       type = nil
       iface[tmp_int]["ring_params"] = {}
       so.stdout.lines.each do |line|
@@ -462,7 +462,7 @@ Ohai.plugin(:Network) do
     else
       default_route_table = configuration(:default_route_table)
     end
-    Ohai::Log.debug("default route table is '#{default_route_table}'")
+    Ohai::Log.debug("Plugin Network: default route table is '#{default_route_table}'")
 
     # Match the lead line for an interface from iproute2
     # 3: eth0.11@eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP
@@ -507,14 +507,14 @@ Ohai.plugin(:Network) do
                            else
                              "default_#{family[:name]}_interface"
                            end
-          Ohai::Log.debug("Unable to determine '#{attribute_name}' as no default routes were found for that interface family")
+          Ohai::Log.debug("Plugin Network: Unable to determine '#{attribute_name}' as no default routes were found for that interface family")
         else
           network["#{default_prefix}_interface"] = default_route[:dev]
-          Ohai::Log.debug("#{default_prefix}_interface set to #{default_route[:dev]}")
+          Ohai::Log.debug("Plugin Network: #{default_prefix}_interface set to #{default_route[:dev]}")
 
           # setting gateway to 0.0.0.0 or :: if the default route is a link level one
           network["#{default_prefix}_gateway"] = default_route[:via] ? default_route[:via] : family[:default_route].chomp("/0")
-          Ohai::Log.debug("#{default_prefix}_gateway set to #{network["#{default_prefix}_gateway"]}")
+          Ohai::Log.debug("Plugin Network: #{default_prefix}_gateway set to #{network["#{default_prefix}_gateway"]}")
 
           # deduce the default route the user most likely cares about to pick {ip,mac,ip6}address below
           favored_route = favored_default_route(routes, iface, default_route, family)
@@ -527,20 +527,20 @@ Ohai.plugin(:Network) do
             if family[:name] == "inet"
               ipaddress favored_route[:src]
               m = get_mac_for_interface(iface, favored_route[:dev])
-              Ohai::Log.debug("Overwriting macaddress #{macaddress} with #{m} from interface #{favored_route[:dev]}") if macaddress
+              Ohai::Log.debug("Plugin Network: Overwriting macaddress #{macaddress} with #{m} from interface #{favored_route[:dev]}") if macaddress
               macaddress m
             elsif family[:name] == "inet6"
               # this rarely does anything since we rarely have src for ipv6, so this usually falls back on the network plugin
               ip6address favored_route[:src]
               if macaddress
-                Ohai::Log.debug("Not setting macaddress from ipv6 interface #{favored_route[:dev]} because macaddress is already set")
+                Ohai::Log.debug("Plugin Network: Not setting macaddress from ipv6 interface #{favored_route[:dev]} because macaddress is already set")
               else
                 macaddress get_mac_for_interface(iface, favored_route[:dev])
               end
             end
           else
-            Ohai::Log.debug("the linux/network plugin was unable to deduce the favored default route for family '#{family[:name]}' despite finding a default route, and is not setting ipaddress/ip6address/macaddress. the network plugin may provide fallbacks.")
-            Ohai::Log.debug("this potential default route was excluded: #{default_route}")
+            Ohai::Log.debug("Plugin Network: Unable to deduce the favored default route for family '#{family[:name]}' despite finding a default route, and is not setting ipaddress/ip6address/macaddress. the network plugin may provide fallbacks.")
+            Ohai::Log.debug("Plugin Network: This potential default route was excluded: #{default_route}")
           end
         end
       end # end families.each
@@ -550,7 +550,7 @@ Ohai.plugin(:Network) do
         route_result = so.stdout.split($/).grep( /^0.0.0.0/ )[0].split( /[ \t]+/ )
         network[:default_gateway], network[:default_interface] = route_result.values_at(1, 7)
       rescue Ohai::Exceptions::Exec
-        Ohai::Log.debug("Unable to determine default interface")
+        Ohai::Log.debug("Plugin Network: Unable to determine default interface")
       end
 
       so = shell_out("ifconfig -a")
diff --git a/lib/ohai/plugins/linux/sessions.rb b/lib/ohai/plugins/linux/sessions.rb
index a2a3a09b..7fb2b5ae 100644
--- a/lib/ohai/plugins/linux/sessions.rb
+++ b/lib/ohai/plugins/linux/sessions.rb
@@ -45,6 +45,8 @@ Ohai.plugin(:Sessions) do
           sessions[:by_user][user] = [s]
         end
       end
+    else
+      Ohai::Log.debug("Plugin Sessions: Could not find loginctl. Skipping plugin.")
     end
   end
 end
diff --git a/lib/ohai/plugins/linux/virtualization.rb b/lib/ohai/plugins/linux/virtualization.rb
index ec101314..a0409472 100644
--- a/lib/ohai/plugins/linux/virtualization.rb
+++ b/lib/ohai/plugins/linux/virtualization.rb
@@ -49,6 +49,7 @@ Ohai.plugin(:Virtualization) do
       # This file should exist on most Xen systems, normally empty for guests
       if File.exist?("/proc/xen/capabilities")
         if File.read("/proc/xen/capabilities") =~ /control_d/i
+          Ohai::Log.debug("Plugin Virtualization: /proc/xen/capabilities contains control_d. Detecting as Xen host")
           virtualization[:role] = "host"
           virtualization[:systems][:xen] = "host"
         end
@@ -65,10 +66,12 @@ Ohai.plugin(:Virtualization) do
     if File.exist?("/proc/modules")
       modules = File.read("/proc/modules")
       if modules =~ /^vboxdrv/
+        Ohai::Log.debug("Plugin Virtualization: /proc/modules contains vboxdrv. Detecting as vbox host")
         virtualization[:system] = "vbox"
         virtualization[:role] = "host"
         virtualization[:systems][:vbox] = "host"
       elsif modules =~ /^vboxguest/
+        Ohai::Log.debug("Plugin Virtualization: /proc/modules contains vboxguest. Detecting as vbox guest")
         virtualization[:system] = "vbox"
         virtualization[:role] = "guest"
         virtualization[:systems][:vbox] = "guest"
@@ -77,6 +80,7 @@ Ohai.plugin(:Virtualization) do
 
     # if nova binary is present we're on an openstack host
     if nova_exists?
+      Ohai::Log.debug("Plugin Virtualization: nova command exists. Detecting as openstack host")
       virtualization[:system] = "openstack"
       virtualization[:role] = "host"
       virtualization[:systems][:openstack] = "host"
@@ -85,6 +89,7 @@ Ohai.plugin(:Virtualization) do
     # Detect paravirt KVM/QEMU from cpuinfo, report as KVM
     if File.exist?("/proc/cpuinfo")
       if File.read("/proc/cpuinfo") =~ /QEMU Virtual CPU|Common KVM processor|Common 32-bit KVM processor/
+        Ohai::Log.debug("Plugin Virtualization: /proc/cpuinfo lists a KVM paravirt CPU string. Detecting as kvm guest")
         virtualization[:system] = "kvm"
         virtualization[:role] = "guest"
         virtualization[:systems][:kvm] = "guest"
@@ -96,9 +101,11 @@ Ohai.plugin(:Virtualization) do
     if File.exist?("/sys/devices/virtual/misc/kvm")
       virtualization[:system] = "kvm"
       if File.read("/proc/cpuinfo") =~ /hypervisor/
+        Ohai::Log.debug("Plugin Virtualization: /sys/devices/virtual/misc/kvm present and /proc/cpuinfo lists the hypervisor feature. Detecting as kvm guest")
         virtualization[:role] = "guest"
         virtualization[:systems][:kvm] = "guest"
       else
+        Ohai::Log.debug("Plugin Virtualization: /sys/devices/virtual/misc/kvm present and /proc/cpuinfo does not list the hypervisor feature. Detecting as kvm host")
         virtualization[:role] = "host"
         virtualization[:systems][:kvm] = "host"
       end
@@ -107,10 +114,12 @@ Ohai.plugin(:Virtualization) do
     # Detect OpenVZ / Virtuozzo.
     # http://wiki.openvz.org/BC_proc_entries
     if File.exist?("/proc/bc/0")
+      Ohai::Log.debug("Plugin Virtualization: /proc/bc/0 exists. Detecting as openvz host")
       virtualization[:system] = "openvz"
       virtualization[:role] = "host"
       virtualization[:systems][:openvz] = "host"
     elsif File.exist?("/proc/vz")
+      Ohai::Log.debug("Plugin Virtualization: /proc/vz exists. Detecting as openvz guest")
       virtualization[:system] = "openvz"
       virtualization[:role] = "guest"
       virtualization[:systems][:openvz] = "guest"
@@ -119,6 +128,7 @@ Ohai.plugin(:Virtualization) do
     # Detect Parallels virtual machine from pci devices
     if File.exist?("/proc/bus/pci/devices")
       if File.read("/proc/bus/pci/devices") =~ /1ab84000/
+        Ohai::Log.debug("Plugin Virtualization: /proc/bus/pci/devices contains '1ab84000' pci device. Detecting as parallels guest")
         virtualization[:system] = "parallels"
         virtualization[:role] = "guest"
         virtualization[:systems][:parallels] = "guest"
@@ -129,6 +139,7 @@ Ohai.plugin(:Virtualization) do
     if File.exist?("/usr/sbin/dmidecode")
       guest = guest_from_dmi(shell_out("dmidecode").stdout)
       if guest
+        Ohai::Log.debug("Plugin Virtualization: dmidecode contains string indicating #{guest} guest")
         virtualization[:system] = guest
         virtualization[:role] = "guest"
         virtualization[:systems][guest.to_sym] = "guest"
@@ -142,9 +153,11 @@ Ohai.plugin(:Virtualization) do
       if vxid && vxid[2]
         virtualization[:system] = "linux-vserver"
         if vxid[2] == "0"
+          Ohai::Log.debug("Plugin Virtualization: /proc/self/status contains 's_context' or 'VxID' with a value of 0. Detecting as linux-vserver host")
           virtualization[:role] = "host"
           virtualization[:systems]["linux-vserver"] = "host"
         else
+          Ohai::Log.debug("Plugin Virtualization: /proc/self/status contains 's_context' or 'VxID' with a non-0 value. Detecting as linux-vserver guest")
           virtualization[:role] = "guest"
           virtualization[:systems]["linux-vserver"] = "guest"
         end
@@ -173,6 +186,7 @@ Ohai.plugin(:Virtualization) do
       cgroup_content = File.read("/proc/self/cgroup")
       if cgroup_content =~ %r{^\d+:[^:]+:/(lxc|docker)/.+$} ||
           cgroup_content =~ %r{^\d+:[^:]+:/[^/]+/(lxc|docker)-.+$}
+        Ohai::Log.debug("Plugin Virtualization: /proc/self/cgroup indicates #{$1} container. Detecting as #{$1} guest")
         virtualization[:system] = $1
         virtualization[:role] = "guest"
         virtualization[:systems][$1.to_sym] = "guest"
@@ -181,6 +195,7 @@ Ohai.plugin(:Virtualization) do
         # Even so, it is likely we are on an LXC capable host that is not being used as such
         # So we're cautious here to not overwrite other existing values (OHAI-573)
         unless virtualization[:system] && virtualization[:role]
+          Ohai::Log.debug("Plugin Virtualization: /proc/self/cgroup and lxc-version command exist. Detecting as lxc host")
           virtualization[:system] = "lxc"
           virtualization[:role] = "host"
         end
@@ -190,6 +205,7 @@ Ohai.plugin(:Virtualization) do
         virtualization[:systems][:lxc] = "host"
       end
     elsif File.exist?("/.dockerenv") || File.exist?("/.dockerinit")
+      Ohai::Log.debug("Plugin Virtualization: .dockerenv or .dockerinit exist. Detecting as docker guest")
       virtualization[:system] = "docker"
       virtualization[:role] = "guest"
       virtualization[:systems][:docker] = "guest"
@@ -198,9 +214,11 @@ Ohai.plugin(:Virtualization) do
     # Detect LXD
     # See https://github.com/lxc/lxd/blob/master/doc/dev-lxd.md
     if File.exist?("/dev/lxd/sock")
+      Ohai::Log.debug("Plugin Virtualization: /dev/lxd/sock exists. Detecting as lxd guest")
       virtualization[:system] = "lxd"
       virtualization[:role] = "guest"
     elsif File.exist?("/var/lib/lxd/devlxd")
+      Ohai::Log.debug("Plugin Virtualization: /var/lib/lxd/devlxd exists. Detecting as lxd host")
       virtualization[:system] = "lxd"
       virtualization[:role] = "host"
     end
diff --git a/lib/ohai/plugins/lua.rb b/lib/ohai/plugins/lua.rb
index 0a6aaeab..8c1ff496 100644
--- a/lib/ohai/plugins/lua.rb
+++ b/lib/ohai/plugins/lua.rb
@@ -31,7 +31,7 @@ Ohai.plugin(:Lua) do
         languages[:lua] = lua if lua[:version]
       end
     rescue Ohai::Exceptions::Exec
-      Ohai::Log.debug('Lua plugin: Could not shell_out "lua -v". Skipping plugin')
+      Ohai::Log.debug('Plugin Lua: Could not shell_out "lua -v". Skipping plugin')
     end
   end
 end
diff --git a/lib/ohai/plugins/network.rb b/lib/ohai/plugins/network.rb
index 1a1175f5..91547d19 100644
--- a/lib/ohai/plugins/network.rb
+++ b/lib/ohai/plugins/network.rb
@@ -77,13 +77,13 @@ Ohai.plugin(:NetworkAddresses) do
         v[:iface] == network[int_attr]
       end
       if gw_if_ips.empty?
-        Ohai::Log.warn("[#{family}] no ip address on #{network[int_attr]}")
+        Ohai::Log.warn("Plugin Network: [#{family}] no ip address on #{network[int_attr]}")
       elsif network[gw_attr] &&
           network["interfaces"][network[int_attr]] &&
           network["interfaces"][network[int_attr]]["addresses"]
         if [ "0.0.0.0", "::", /^fe80:/ ].any? { |pat| pat === network[gw_attr] }
           # link level default route
-          Ohai::Log.debug("link level default #{family} route, picking ip from #{network[gw_attr]}")
+          Ohai::Log.debug("Plugin Network: link level default #{family} route, picking ip from #{network[gw_attr]}")
           r = gw_if_ips.first
         else
           # checking network masks
@@ -92,9 +92,9 @@ Ohai.plugin(:NetworkAddresses) do
           end.first
           if r.nil?
             r = gw_if_ips.first
-            Ohai::Log.debug("[#{family}] no ipaddress/mask on #{network[int_attr]} matching the gateway #{network[gw_attr]}, picking #{r[:ipaddress]}")
+            Ohai::Log.debug("Plugin Network: [#{family}] no ipaddress/mask on #{network[int_attr]} matching the gateway #{network[gw_attr]}, picking #{r[:ipaddress]}")
           else
-            Ohai::Log.debug("[#{family}] Using default interface #{network[int_attr]} and default gateway #{network[gw_attr]} to set the default ip to #{r[:ipaddress]}")
+            Ohai::Log.debug("Plugin Network: [#{family}] Using default interface #{network[int_attr]} and default gateway #{network[gw_attr]} to set the default ip to #{r[:ipaddress]}")
           end
         end
       else
@@ -103,7 +103,7 @@ Ohai.plugin(:NetworkAddresses) do
       end
     else
       r = ips.first
-      Ohai::Log.debug("[#{family}] no default interface, picking the first ipaddress")
+      Ohai::Log.debug("Plugin Network: [#{family}] no default interface, picking the first ipaddress")
     end
 
     return [ nil, nil ] if r.nil? || r.empty?
@@ -149,13 +149,13 @@ Ohai.plugin(:NetworkAddresses) do
       # don't overwrite attributes if they've already been set by the "#{os}::network" plugin
       if (family == "inet") && ipaddress.nil?
         if r["ip"].nil?
-          Ohai::Log.warn("unable to detect ipaddress")
+          Ohai::Log.warn("Plugin Network: unable to detect ipaddress")
         else
           ipaddress r["ip"]
         end
       elsif (family == "inet6") && ip6address.nil?
         if r["ip"].nil?
-          Ohai::Log.debug("unable to detect ip6address")
+          Ohai::Log.debug("Plugin Network: unable to detect ip6address")
         else
           ip6address r["ip"]
         end
@@ -165,10 +165,10 @@ Ohai.plugin(:NetworkAddresses) do
       # otherwise we set macaddress on a first-found basis (and we started with ipv4)
       if macaddress.nil?
         if r["mac"]
-          Ohai::Log.debug("setting macaddress to '#{r["mac"]}' from interface '#{r["iface"]}' for family '#{family}'")
+          Ohai::Log.debug("Plugin Network: setting macaddress to '#{r["mac"]}' from interface '#{r["iface"]}' for family '#{family}'")
           macaddress r["mac"]
         else
-          Ohai::Log.debug("unable to detect macaddress for family '#{family}'")
+          Ohai::Log.debug("Plugin Network: unable to detect macaddress for family '#{family}'")
         end
       end
 
@@ -177,7 +177,7 @@ Ohai.plugin(:NetworkAddresses) do
 
     if results["inet"]["iface"] && results["inet6"]["iface"] &&
         (results["inet"]["iface"] != results["inet6"]["iface"])
-      Ohai::Log.debug("ipaddress and ip6address are set from different interfaces (#{results["inet"]["iface"]} & #{results["inet6"]["iface"]})")
+      Ohai::Log.debug("Plugin Network: ipaddress and ip6address are set from different interfaces (#{results["inet"]["iface"]} & #{results["inet6"]["iface"]})")
     end
   end
 end
diff --git a/lib/ohai/plugins/scala.rb b/lib/ohai/plugins/scala.rb
index f847a565..ee905a64 100644
--- a/lib/ohai/plugins/scala.rb
+++ b/lib/ohai/plugins/scala.rb
@@ -28,7 +28,7 @@ Ohai.plugin(:Scala) do
         scala[:version] = so.stderr.split[4]
       end
     rescue Ohai::Exceptions::Exec
-      Ohai::Log.debug('Scala plugin: Could not shell_out "scala -version". Skipping data')
+      Ohai::Log.debug('Plugin Scala: Could not shell_out "scala -version". Skipping data')
     end
 
     # Check for sbt
@@ -40,7 +40,7 @@ Ohai.plugin(:Scala) do
         scala[:sbt][:version] = so.stdout.split[3]
       end
     rescue Ohai::Exceptions::Exec
-      Ohai::Log.debug('Scala plugin: Could not shell_out "sbt --version". Skipping data')
+      Ohai::Log.debug('Plugin Scala: Could not shell_out "sbt --version". Skipping data')
     end
 
     languages[:scala] = scala unless scala.empty?
diff --git a/lib/ohai/plugins/solaris2/dmi.rb b/lib/ohai/plugins/solaris2/dmi.rb
index 3f98dbfe..32f935db 100644
--- a/lib/ohai/plugins/solaris2/dmi.rb
+++ b/lib/ohai/plugins/solaris2/dmi.rb
@@ -153,7 +153,7 @@ Ohai.plugin(:DMI) do
 
       elsif data = data_key_value_line.match(line)
         if dmi_record == nil
-          Ohai::Log.debug("unexpected data line found before header; discarding:\n#{line}")
+          Ohai::Log.debug("Plugin DMI: unexpected data line found before header; discarding:\n#{line}")
           next
         end
         dmi[dmi_record[:type]][:all_records][dmi_record[:position]][data[1]] = data[2]
@@ -161,7 +161,7 @@ Ohai.plugin(:DMI) do
 
       elsif data = data_key_only_line.match(line)
         if dmi_record == nil
-          Ohai::Log.debug("unexpected data line found before header; discarding:\n#{line}")
+          Ohai::Log.debug("Plugin DMI: unexpected data line found before header; discarding:\n#{line}")
           next
         end
         dmi[dmi_record[:type]][:all_records][dmi_record[:position]][data[1]] = ""
@@ -169,11 +169,11 @@ Ohai.plugin(:DMI) do
 
       elsif extended_data = extended_data_line.match(line)
         if dmi_record == nil
-          Ohai::Log.debug("unexpected extended data line found before header; discarding:\n#{line}")
+          Ohai::Log.debug("Plugin DMI: unexpected extended data line found before header; discarding:\n#{line}")
           next
         end
         if field == nil
-          Ohai::Log.debug("unexpected extended data line found outside data section; discarding:\n#{line}")
+          Ohai::Log.debug("Plugin DMI: unexpected extended data line found outside data section; discarding:\n#{line}")
           next
         end
         # overwrite "raw" value with a new Mash
@@ -181,7 +181,7 @@ Ohai.plugin(:DMI) do
         dmi[dmi_record[:type]][:all_records][dmi_record[:position]][field][extended_data[1]] = extended_data[2]
 
       else
-        Ohai::Log.debug("unrecognized output line; discarding:\n#{line}")
+        Ohai::Log.debug("Plugin DMI: unrecognized output line; discarding:\n#{line}")
 
       end
     end
diff --git a/lib/ohai/plugins/virtualbox.rb b/lib/ohai/plugins/virtualbox.rb
index 435f649f..36558552 100644
--- a/lib/ohai/plugins/virtualbox.rb
+++ b/lib/ohai/plugins/virtualbox.rb
@@ -20,25 +20,30 @@ Ohai.plugin(:Virtualbox) do
   provides "virtualbox"
 
   collect_data do
-    so = shell_out("VBoxControl guestproperty enumerate")
-    if so.exitstatus == 0
-      virtualbox Mash.new
-      virtualbox[:host] = Mash.new
-      virtualbox[:guest] = Mash.new
-      so.stdout.lines.each do |line|
-        case line
-        when /LanguageID, value: (\S*),/
-          virtualbox[:host][:language] = Regexp.last_match(1)
-        when /VBoxVer, value: (\S*),/
-          virtualbox[:host][:version] = Regexp.last_match(1)
-        when /VBoxRev, value: (\S*),/
-          virtualbox[:host][:revision] = Regexp.last_match(1)
-        when /GuestAdd\/VersionExt, value: (\S*),/
-          virtualbox[:guest][:guest_additions_version] = Regexp.last_match(1)
-        when /GuestAdd\/Revision, value: (\S*),/
-          virtualbox[:guest][:guest_additions_revision] = Regexp.last_match(1)
+    begin
+      so = shell_out("VBoxControl guestproperty enumerate")
+
+      if so.exitstatus == 0
+        virtualbox Mash.new
+        virtualbox[:host] = Mash.new
+        virtualbox[:guest] = Mash.new
+        so.stdout.lines.each do |line|
+          case line
+          when /LanguageID, value: (\S*),/
+            virtualbox[:host][:language] = Regexp.last_match(1)
+          when /VBoxVer, value: (\S*),/
+            virtualbox[:host][:version] = Regexp.last_match(1)
+          when /VBoxRev, value: (\S*),/
+            virtualbox[:host][:revision] = Regexp.last_match(1)
+          when /GuestAdd\/VersionExt, value: (\S*),/
+            virtualbox[:guest][:guest_additions_version] = Regexp.last_match(1)
+          when /GuestAdd\/Revision, value: (\S*),/
+            virtualbox[:guest][:guest_additions_revision] = Regexp.last_match(1)
+          end
         end
       end
+    rescue Ohai::Exceptions::Exec
+      Ohai::Log.debug('Plugin Virtualbox: Could not execute "VBoxControl guestproperty enumerate". Skipping data')
     end
   end
 end
diff --git a/lib/ohai/plugins/vmware.rb b/lib/ohai/plugins/vmware.rb
index 53327e41..73b2505d 100644
--- a/lib/ohai/plugins/vmware.rb
+++ b/lib/ohai/plugins/vmware.rb
@@ -42,7 +42,7 @@ Ohai.plugin(:VMware) do
 
   def get_vm_attributes(vmtools_path)
     if !File.exist?(vmtools_path)
-      Ohai::Log.debug("#{vmtools_path} not found")
+      Ohai::Log.debug("Plugin VMware: #{vmtools_path} not found")
     else
       vmware Mash.new
       begin
@@ -62,7 +62,7 @@ Ohai.plugin(:VMware) do
           vmware[param] = from_cmd("#{vmtools_path} #{param} status")
         end
       rescue
-        Ohai::Log.debug("Error while collecting VMware guest attributes")
+        Ohai::Log.debug("Plugin VMware: Error while collecting VMware guest attributes")
       end
     end
   end
diff --git a/lib/ohai/util/file_helper.rb b/lib/ohai/util/file_helper.rb
index 5b08e2db..eb9a12e9 100644
--- a/lib/ohai/util/file_helper.rb
+++ b/lib/ohai/util/file_helper.rb
@@ -26,11 +26,11 @@ module Ohai
         paths.each do |path|
           filename = File.join(path, cmd)
           if File.executable?(filename)
-            Ohai::Log.debug("#{self.name} plugin: found #{cmd} at #{filename}")
+            Ohai::Log.debug("Plugin #{self.name}: found #{cmd} at #{filename}")
             return filename
           end
         end
-        Ohai::Log.debug("#{self.name} plugin: did not find #{cmd}")
+        Ohai::Log.debug("Plugin #{self.name}: did not find #{cmd}")
         false
       end
     end
diff --git a/spec/unit/plugins/linux/network_spec.rb b/spec/unit/plugins/linux/network_spec.rb
index 6e78997f..4b88ebe2 100644
--- a/spec/unit/plugins/linux/network_spec.rb
+++ b/spec/unit/plugins/linux/network_spec.rb
@@ -1325,7 +1325,7 @@ EOM
         end
 
         it "logs a message and skips previously unseen interfaces in 'ip route show'" do
-          expect(Ohai::Log).to receive(:debug).with("Skipping previously unseen interface from 'ip route show': virbr0").once
+          expect(Ohai::Log).to receive(:debug).with(/Skipping previously unseen interface from 'ip route show': virbr0/).once
           allow(Ohai::Log).to receive(:debug) # Catches the 'Loading plugin network' type messages
           plugin.run
         end
diff --git a/spec/unit/plugins/network_spec.rb b/spec/unit/plugins/network_spec.rb
index 60d4cac6..31780b57 100644
--- a/spec/unit/plugins/network_spec.rb
+++ b/spec/unit/plugins/network_spec.rb
@@ -367,7 +367,7 @@ describe Ohai::System, "Network Plugin" do
           end
 
           it "informs about this setup" do
-            expect(Ohai::Log).to receive(:debug).with(/^ipaddress and ip6address are set from different interfaces/)
+            expect(Ohai::Log).to receive(:debug).with(/ipaddress and ip6address are set from different interfaces/)
             allow(Ohai::Log).to receive(:debug)
             @plugin.run
           end
@@ -396,7 +396,7 @@ describe Ohai::System, "Network Plugin" do
           end
 
           it "informs about this setup" do
-            expect(Ohai::Log).to receive(:debug).with(/^ipaddress and ip6address are set from different interfaces/)
+            expect(Ohai::Log).to receive(:debug).with(/ipaddress and ip6address are set from different interfaces/)
             allow(Ohai::Log).to receive(:debug)
             @plugin.run
           end
@@ -421,8 +421,8 @@ describe Ohai::System, "Network Plugin" do
           end
 
           it "warns about this conflict" do
-            expect(Ohai::Log).to receive(:debug).with(/^\[inet\] no ipaddress\/mask on eth1/).once
-            expect(Ohai::Log).to receive(:debug).with(/^\[inet6\] no ipaddress\/mask on eth1/).once
+            expect(Ohai::Log).to receive(:debug).with(/\[inet\] no ipaddress\/mask on eth1/).once
+            expect(Ohai::Log).to receive(:debug).with(/\[inet6\] no ipaddress\/mask on eth1/).once
             allow(Ohai::Log).to receive(:debug)
             @plugin.run
           end
@@ -460,11 +460,11 @@ describe Ohai::System, "Network Plugin" do
           end
 
           it "warns about this conflict" do
-            expect(Ohai::Log).to receive(:warn).with(/^unable to detect ipaddress/).once
-            expect(Ohai::Log).to receive(:warn).with(/^\[inet\] no ip address on eth0/).once
-            expect(Ohai::Log).to receive(:debug).with(/^unable to detect ip6address/).once
-            expect(Ohai::Log).to receive(:debug).with(/^unable to detect macaddress/).twice # for each family
-            expect(Ohai::Log).to receive(:warn).with(/^\[inet6\] no ip address on eth0/).once
+            expect(Ohai::Log).to receive(:warn).with(/unable to detect ipaddress/).once
+            expect(Ohai::Log).to receive(:warn).with(/\[inet\] no ip address on eth0/).once
+            expect(Ohai::Log).to receive(:debug).with(/unable to detect ip6address/).once
+            expect(Ohai::Log).to receive(:debug).with(/unable to detect macaddress/).twice # for each family
+            expect(Ohai::Log).to receive(:warn).with(/\[inet6\] no ip address on eth0/).once
             @plugin.run
           end
         end
@@ -491,9 +491,9 @@ describe Ohai::System, "Network Plugin" do
           end
 
           it "should warn about it" do
-            expect(Ohai::Log).to receive(:warn).with(/^unable to detect ipaddress/).once
-            expect(Ohai::Log).to receive(:debug).with(/^unable to detect macaddress/).twice # for each family
-            expect(Ohai::Log).to receive(:debug).with(/^unable to detect ip6address/).once
+            expect(Ohai::Log).to receive(:warn).with(/unable to detect ipaddress/).once
+            expect(Ohai::Log).to receive(:debug).with(/unable to detect macaddress/).twice # for each family
+            expect(Ohai::Log).to receive(:debug).with(/unable to detect ip6address/).once
             @plugin.run
           end
         end
@@ -643,8 +643,8 @@ describe Ohai::System, "Network Plugin" do
           it_populates_ipaddress_attributes
 
           it "picks {ip,mac,ip6}address from the first interface" do
-            expect(Ohai::Log).to receive(:debug).with(/^\[inet\] no default interface/).once
-            expect(Ohai::Log).to receive(:debug).with(/^\[inet6\] no default interface/).once
+            expect(Ohai::Log).to receive(:debug).with(/\[inet\] no default interface/).once
+            expect(Ohai::Log).to receive(:debug).with(/\[inet6\] no default interface/).once
             allow(Ohai::Log).to receive(:debug)
             @plugin.run
             expect(@plugin["ipaddress"]).to eq("192.168.99.11")
@@ -666,8 +666,8 @@ describe Ohai::System, "Network Plugin" do
           it_populates_ipaddress_attributes
 
           it "prefers global scope addressses to set {ip,mac,ip6}address" do
-            expect(Ohai::Log).to receive(:debug).with(/^\[inet\] no default interface/).once
-            expect(Ohai::Log).to receive(:debug).with(/^\[inet6\] no default interface/).once
+            expect(Ohai::Log).to receive(:debug).with(/\[inet\] no default interface/).once
+            expect(Ohai::Log).to receive(:debug).with(/\[inet6\] no default interface/).once
             allow(Ohai::Log).to receive(:debug)
             @plugin.run
             expect(@plugin["ipaddress"]).to eq("192.168.99.11")
@@ -795,10 +795,10 @@ describe Ohai::System, "Network Plugin" do
         end
 
         it "warns about not being able to set {ip,mac}address (ipv4)" do
-          expect(Ohai::Log).to receive(:warn).with(/^unable to detect ipaddress/).once
-          expect(Ohai::Log).to receive(:debug).with(/^unable to detect macaddress/) # for ipv4
-          expect(Ohai::Log).to receive(:debug).with(/^setting macaddress to/) # for ipv6
-          expect(Ohai::Log).to receive(:debug).with(/^\[inet6\] Using default interface eth0 and default gateway/) # for ipv6
+          expect(Ohai::Log).to receive(:warn).with(/unable to detect ipaddress/).once
+          expect(Ohai::Log).to receive(:debug).with(/unable to detect macaddress/) # for ipv4
+          expect(Ohai::Log).to receive(:debug).with(/setting macaddress to/) # for ipv6
+          expect(Ohai::Log).to receive(:debug).with(/\[inet6\] Using default interface eth0 and default gateway/) # for ipv6
           @plugin.run
         end
 
@@ -810,7 +810,7 @@ describe Ohai::System, "Network Plugin" do
         end
 
         it "informs about macaddress being set using the ipv6 setup" do
-          expect(Ohai::Log).to receive(:debug).with(/^setting macaddress to '00:16:3E:2F:36:79'/)
+          expect(Ohai::Log).to receive(:debug).with(/setting macaddress to '00:16:3E:2F:36:79'/)
           allow(Ohai::Log).to receive(:debug)
           @plugin.run
         end
@@ -842,7 +842,7 @@ describe Ohai::System, "Network Plugin" do
         end
 
         it "informs about macaddress being set using the ipv6 setup" do
-          expect(Ohai::Log).to receive(:debug).with(/^setting macaddress to '00:16:3E:2F:36:79'/)
+          expect(Ohai::Log).to receive(:debug).with(/setting macaddress to '00:16:3E:2F:36:79'/)
           allow(Ohai::Log).to receive(:debug)
           @plugin.run
         end
@@ -962,7 +962,7 @@ describe Ohai::System, "Network Plugin" do
             end
 
             it "warns about not being able to set ipaddress" do
-              expect(Ohai::Log).to receive(:warn).with(/^unable to detect ipaddress/).once
+              expect(Ohai::Log).to receive(:warn).with(/unable to detect ipaddress/).once
               @plugin.run
             end