diff --git a/lib/vmpooler/api.rb b/lib/vmpooler/api.rb
index 9ffe386..7d72ec6 100644
--- a/lib/vmpooler/api.rb
+++ b/lib/vmpooler/api.rb
@@ -38,8 +38,8 @@ module Vmpooler
         # Using customised collector that filters out hostnames on API paths
         require 'vmpooler/metrics/promstats/collector_middleware'
         require 'prometheus/middleware/exporter'
-        use Vmpooler::Metrics::Promstats::CollectorMiddleware, metrics_prefix: "#{metrics.metrics_prefix}_http"
-        use Prometheus::Middleware::Exporter, path: metrics.endpoint
+        use Vmpooler::Metrics::Promstats::CollectorMiddleware, metrics_prefix: "#{metrics.prometheus_prefix}_http"
+        use Prometheus::Middleware::Exporter, path: metrics.prometheus_endpoint
       end
 
       if torun.include? :api
diff --git a/lib/vmpooler/api/v1.rb b/lib/vmpooler/api/v1.rb
index 8c150ff..066af86 100644
--- a/lib/vmpooler/api/v1.rb
+++ b/lib/vmpooler/api/v1.rb
@@ -89,18 +89,16 @@ module Vmpooler
         template_backends += aliases
         weighted_pools = get_pool_weights(template_backends)
 
-        pickup = Pickup.new(weighted_pools) if weighted_pools.count == template_backends.count
-        count.to_i.times do
-          if pickup
+        if weighted_pools.count > 1 && weighted_pools.count == template_backends.count
+          pickup = Pickup.new(weighted_pools)
+          count.to_i.times do
             selection << pickup.pick
-          else
+          end
+        else
+          count.to_i.times do
             selection << template_backends.sample
           end
         end
-      else
-        count.to_i.times do
-          selection << template
-        end
       end
 
       count_selection(selection)
@@ -809,7 +807,7 @@ module Vmpooler
 
     post "#{api_prefix}/ondemandvm/?" do
       content_type :json
-      metrics.increment('api_vm.post.ondemand.requestid')
+      metrics.increment('http_requests_vm_total.post.ondemand.requestid')
 
       need_token! if Vmpooler::API.settings.config[:auth]
 
@@ -847,7 +845,7 @@ module Vmpooler
     post "#{api_prefix}/ondemandvm/:template/?" do
       content_type :json
       result = { 'ok' => false }
-      metrics.increment('api_vm.delete.ondemand.template')
+      metrics.increment('http_requests_vm_total.delete.ondemand.template')
 
       need_token! if Vmpooler::API.settings.config[:auth]
 
@@ -874,7 +872,7 @@ module Vmpooler
 
     get "#{api_prefix}/ondemandvm/:requestid/?" do
       content_type :json
-      metrics.increment('api_vm.get.ondemand.request')
+      metrics.increment('http_requests_vm_total.get.ondemand.request')
 
       status 404
       result = check_ondemand_request(params[:requestid])
@@ -885,7 +883,7 @@ module Vmpooler
     delete "#{api_prefix}/ondemandvm/:requestid/?" do
       content_type :json
       need_token! if Vmpooler::API.settings.config[:auth]
-      metrics.increment('api_vm.delete.ondemand.request')
+      metrics.increment('http_requests_vm_total.delete.ondemand.request')
 
       status 404
       result = delete_ondemand_request(params[:requestid])
@@ -896,7 +894,7 @@ module Vmpooler
     post "#{api_prefix}/vm/?" do
       content_type :json
       result = { 'ok' => false }
-      metrics.increment('api_vm.post.vm.checkout')
+      metrics.increment('http_requests_vm_total.post.vm.checkout')
 
       payload = JSON.parse(request.body.read)
 
@@ -1051,7 +1049,7 @@ module Vmpooler
     post "#{api_prefix}/vm/:template/?" do
       content_type :json
       result = { 'ok' => false }
-      metrics.increment('api_vm.get.vm.template')
+      metrics.increment('http_requests_vm_total.get.vm.template')
 
       payload = extract_templates_from_query_params(params[:template])
 
@@ -1075,7 +1073,7 @@ module Vmpooler
 
     get "#{api_prefix}/vm/:hostname/?" do
       content_type :json
-      metrics.increment('api_vm.get.vm.hostname')
+      metrics.increment('http_requests_vm_total.get.vm.hostname')
 
       result = {}
 
@@ -1148,7 +1146,7 @@ module Vmpooler
 
     delete "#{api_prefix}/vm/:hostname/?" do
       content_type :json
-      metrics.increment('api_vm.delete.vm.hostname')
+      metrics.increment('http_requests_vm_total.delete.vm.hostname')
 
       result = {}
 
@@ -1177,7 +1175,7 @@ module Vmpooler
 
     put "#{api_prefix}/vm/:hostname/?" do
       content_type :json
-      metrics.increment('api_vm.put.vm.modify')
+      metrics.increment('http_requests_vm_total.put.vm.modify')
 
       status 404
       result = { 'ok' => false }
@@ -1254,7 +1252,7 @@ module Vmpooler
 
     post "#{api_prefix}/vm/:hostname/disk/:size/?" do
       content_type :json
-      metrics.increment('api_vm.post.vm.disksize')
+      metrics.increment('http_requests_vm_total.post.vm.disksize')
 
       need_token! if Vmpooler::API.settings.config[:auth]
 
@@ -1278,7 +1276,7 @@ module Vmpooler
 
     post "#{api_prefix}/vm/:hostname/snapshot/?" do
       content_type :json
-      metrics.increment('api_vm.post.vm.snapshot')
+      metrics.increment('http_requests_vm_total.post.vm.snapshot')
 
       need_token! if Vmpooler::API.settings.config[:auth]
 
@@ -1304,7 +1302,7 @@ module Vmpooler
 
     post "#{api_prefix}/vm/:hostname/snapshot/:snapshot/?" do
       content_type :json
-      metrics.increment('api_vm.post.vm.disksize')
+      metrics.increment('http_requests_vm_total.post.vm.disksize')
 
       need_token! if Vmpooler::API.settings.config[:auth]
 
diff --git a/lib/vmpooler/metrics/promstats.rb b/lib/vmpooler/metrics/promstats.rb
index c7aeb6d..ce1791d 100644
--- a/lib/vmpooler/metrics/promstats.rb
+++ b/lib/vmpooler/metrics/promstats.rb
@@ -5,7 +5,7 @@ require 'prometheus/client'
 module Vmpooler
   class Metrics
     class Promstats < Metrics
-      attr_reader :prefix, :endpoint, :metrics_prefix
+      attr_reader :prefix, :prometheus_endpoint, :prometheus_prefix
 
       # Constants for Metric Types
       M_COUNTER   = 1
@@ -24,22 +24,135 @@ module Vmpooler
 
       def initialize(logger, params = {})
         @prefix = params['prefix'] || 'vmpooler'
-        @metrics_prefix = params['metrics_prefix'] || 'vmpooler'
-        @endpoint = params['endpoint'] || '/prometheus'
+        @prometheus_prefix = params['prometheus_prefix'] || 'vmpooler'
+        @prometheus_endpoint = params['prometheus_endpoint'] || '/prometheus'
         @logger = logger
 
         # Setup up prometheus registry and data structures
         @prometheus = Prometheus::Client.registry
       end
 
-      # Metrics structure used to register the metrics and also translate/interpret the incoming metrics.
+=begin # rubocop:disable Style/BlockComments
+      The Metrics table is used to register metrics and translate/interpret the incoming metrics.
+
+      This table describes all of the prometheus metrics that are recognised by the application.
+      The background documentation for defining metrics is at: https://prometheus.io/docs/introduction/
+      In particular, the naming practices should be adhered to: https://prometheus.io/docs/practices/naming/
+      The Ruby Client docs are also useful: https://github.com/prometheus/client_ruby
+
+      The table here allows the currently used stats definitions to be translated correctly for Prometheus.
+      The current format is of the form A.B.C, where the final fields may be actual values (e.g. poolname).
+      Prometheus metrics cannot use the '.' as a character, so this is either translated into '_' or
+      variable parameters are expressed as labels accompanying the metric.
+
+      Sample statistics are:
+          # Example showing hostnames (FQDN)
+          migrate_from.pix-jj26-chassis1-2.ops.puppetlabs.net
+          migrate_to.pix-jj26-chassis1-8.ops.puppetlabs.net
+
+          # Example showing poolname as a parameter
+          poolreset.invalid.centos-8-x86_64
+
+          # Examples showing similar sub-typed checkout stats
+          checkout.empty.centos-8-x86_64
+          checkout.invalid.centos-8-x86_64
+          checkout.invalid.unknown
+          checkout.success.centos-8-x86_64
+
+          # Stats without any final parameter.
+          connect.fail
+          connect.open
+          delete.failed
+          delete.success
+
+          # Stats with multiple param_labels
+          vmpooler_user.debian-8-x86_64-pixa4.john
+
+        The metrics implementation here preserves the existing framework which will continue to support
+        graphite and statsd (since vmpooler is used outside of puppet). Some rationalisation and renaming
+        of the actual metrics was done to get a more usable model to fit within the prometheus framework.
+        This particularly applies to the user stats collected once individual machines are terminated as
+        this would have challenged prometheus' ability due to multiple (8) parameters being collected
+        in a single measure (which has a very high cardinality).
+
+        Prometheus requires all metrics to be pre-registered (which is the primary reason for this
+        table) and also uses labels to differentiate the characteristics of the measurement. This
+        is used throughout to capture information such as poolnames. So for example, this is a sample
+        of the prometheus metrics generated for the "vmpooler_ready" measurement:
+
+          # TYPE vmpooler_ready gauge
+          # HELP vmpooler_ready vmpooler number of machines in ready State
+          vmpooler_ready{vmpooler_instance="vmpooler",poolname="win-10-ent-x86_64-pixa4"} 2.0
+          vmpooler_ready{vmpooler_instance="vmpooler",poolname="debian-8-x86_64-pixa4"} 2.0
+          vmpooler_ready{vmpooler_instance="vmpooler",poolname="centos-8-x86_64-pixa4"} 2.0
+
+        Prometheus supports the following metric types:
+        (see https://prometheus.io/docs/concepts/metric_types/)
+
+          Counter (increment):
+            A counter is a cumulative metric that represents a single monotonically increasing counter whose
+            value can only increase or be reset to zero on restart
+
+          Gauge:
+            A gauge is a metric that represents a single numerical value that can arbitrarily go up and down.
+
+          Histogram:
+            A histogram samples observations (usually things like request durations or response sizes) and
+            counts them in configurable buckets. It also provides a sum of all observed values.
+            This replaces the timer metric supported by statsd
+
+          Summary :
+            Summary provides a total count of observations and a sum of all observed values, it calculates
+            configurable quantiles over a sliding time window.
+            (Summary is not used in vmpooler)
+
+        vmpooler_metrics_table is a table of hashes, where the hash key represents the first part of the
+        metric name, e.g. for the metric 'delete.*' (see above) the key would be 'delete:'. "Sub-metrics",
+        are supported, again for the 'delete.*' example, this can be subbed into '.failed' and '.success'
+
+        The entries within the hash as are follows:
+
+          mtype:
+            Metric type, which is one of the following constants:
+              M_COUNTER   = 1
+              M_GAUGE     = 2
+              M_SUMMARY   = 3
+              M_HISTOGRAM = 4
+
+          torun:
+            Indicates which process the metric is for - within vmpooler this is either ':api' or ':manager'
+            (there is a suggestion that we change this to two separate tables).
+
+          docstring:
+            Documentation string for the metric - this is displayed as HELP text by the endpoint.
+
+          metric_suffixes:
+            Array of sub-metrics of the form 'sub-metric: "doc-string for sub-metric"'. This supports
+            the generation of individual sub-metrics for all elements in the array.
+
+          param_labels:
+            This is an optional array of symbols for the final labels in a metric. It should not be
+            specified if there are no additional parameters.
+
+            If it specified, it can either be a single symbol, or two or more symbols. The treatment
+            differs if there is only one symbol given as all of the remainder of the metric string
+            supplied is collected into a label with the symbol name. This allows the handling of
+            node names (FQDN).
+
+            To illustrate:
+            1. In the 'connect.*' or 'delete.*' example above, it should not be specified.
+            2. For the 'migrate_from.*' example above, the remainder of the measure is collected
+               as the 'host_name' label.
+            3. For the 'vmpooler_user' example above, the first parameter is treated as the pool
+               name, and the second as the username.
+
+=end
       def vmpooler_metrics_table
         {
           errors: {
             mtype: M_COUNTER,
             torun: %i[manager],
             docstring: 'Count of errors for pool',
-            prom_metric_prefix: "#{@metrics_prefix}_errors",
             metric_suffixes: {
               markedasfailed: 'timeout waiting for instance to initialise',
               duplicatehostname: 'unable to create instance due to duplicate hostname',
@@ -51,42 +164,36 @@ module Vmpooler
             mtype: M_COUNTER,
             torun: %i[manager],
             docstring: 'Number of pool instances this user created created',
-            prom_metric_prefix: "#{@metrics_prefix}_user",
             param_labels: %i[user poolname]
           },
           usage_litmus: {
             mtype: M_COUNTER,
             torun: %i[manager],
             docstring: 'Pools by Litmus job usage',
-            prom_metric_prefix: "#{@metrics_prefix}_usage_litmus",
             param_labels: %i[user poolname]
           },
           usage_jenkins_instance: {
             mtype: M_COUNTER,
             torun: %i[manager],
             docstring: 'Pools by Jenkins instance usage',
-            prom_metric_prefix: "#{@metrics_prefix}_usage_jenkins_instance",
             param_labels: %i[jenkins_instance value_stream poolname]
           },
           usage_branch_project: {
             mtype: M_COUNTER,
             torun: %i[manager],
             docstring: 'Pools by branch/project usage',
-            prom_metric_prefix: "#{@metrics_prefix}_usage_branch_project",
             param_labels: %i[branch project poolname]
           },
           usage_job_component: {
             mtype: M_COUNTER,
             torun: %i[manager],
             docstring: 'Pools by job/component usage',
-            prom_metric_prefix: "#{@metrics_prefix}_usage_job_component",
             param_labels: %i[job_name component_to_test poolname]
           },
           checkout: {
             mtype: M_COUNTER,
             torun: %i[api],
             docstring: 'Pool checkout counts',
-            prom_metric_prefix: "#{@metrics_prefix}_checkout",
             metric_suffixes: {
               nonresponsive: 'checkout failed - non responsive machine',
               empty: 'checkout failed - no machine',
@@ -99,7 +206,6 @@ module Vmpooler
             mtype: M_COUNTER,
             torun: %i[api],
             docstring: 'Delete machine',
-            prom_metric_prefix: "#{@metrics_prefix}_delete",
             metric_suffixes: {
               success: 'succeeded',
               failed: 'failed'
@@ -110,7 +216,6 @@ module Vmpooler
             mtype: M_COUNTER,
             torun: %i[api],
             docstring: 'Ondemand request',
-            prom_metric_prefix: "#{@metrics_prefix}_ondemandrequest_generate",
             metric_suffixes: {
               duplicaterequests: 'failed duplicate request',
               success: 'succeeded'
@@ -121,7 +226,6 @@ module Vmpooler
             mtype: M_COUNTER,
             torun: %i[api],
             docstring: 'Ondemand request failure',
-            prom_metric_prefix: "#{@metrics_prefix}_ondemandrequest_fail",
             metric_suffixes: {
               toomanyrequests: 'too many requests',
               invalid: 'invalid poolname'
@@ -132,7 +236,6 @@ module Vmpooler
             mtype: M_COUNTER,
             torun: %i[api],
             docstring: 'vmpooler pool configuration request',
-            prom_metric_prefix: "#{@metrics_prefix}_config",
             metric_suffixes: { invalid: 'Invalid' },
             param_labels: %i[poolname]
           },
@@ -140,7 +243,6 @@ module Vmpooler
             mtype: M_COUNTER,
             torun: %i[api],
             docstring: 'Pool reset counter',
-            prom_metric_prefix: "#{@metrics_prefix}_poolreset",
             metric_suffixes: { invalid: 'Invalid Pool' },
             param_labels: %i[poolname]
           },
@@ -148,7 +250,6 @@ module Vmpooler
             mtype: M_COUNTER,
             torun: %i[manager],
             docstring: 'vmpooler connect (to vSphere)',
-            prom_metric_prefix: "#{@metrics_prefix}_connect",
             metric_suffixes: {
               open: 'Connect Succeeded',
               fail: 'Connect Failed'
@@ -159,42 +260,36 @@ module Vmpooler
             mtype: M_COUNTER,
             torun: %i[manager],
             docstring: 'vmpooler machine migrated from',
-            prom_metric_prefix: "#{@metrics_prefix}_migrate_from",
             param_labels: %i[host_name]
           },
           migrate_to: {
             mtype: M_COUNTER,
             torun: %i[manager],
             docstring: 'vmpooler machine migrated to',
-            prom_metric_prefix: "#{@metrics_prefix}_migrate_to",
             param_labels: %i[host_name]
           },
-          api_vm: {
+          http_requests_vm_total: {
             mtype: M_COUNTER,
             torun: %i[api],
             docstring: 'Total number of HTTP request/sub-operations handled by the Rack application under the /vm endpoint',
-            prom_metric_prefix: "#{@metrics_prefix}_http_requests_vm_total",
             param_labels: %i[method subpath operation]
           },
           ready: {
             mtype: M_GAUGE,
             torun: %i[manager],
             docstring: 'vmpooler number of machines in ready State',
-            prom_metric_prefix: "#{@metrics_prefix}_ready",
             param_labels: %i[poolname]
           },
           running: {
             mtype: M_GAUGE,
             torun: %i[manager],
             docstring: 'vmpooler number of machines running',
-            prom_metric_prefix: "#{@metrics_prefix}_running",
             param_labels: %i[poolname]
           },
           connection_available: {
             mtype: M_GAUGE,
             torun: %i[manager],
             docstring: 'vmpooler redis connections available',
-            prom_metric_prefix: "#{@metrics_prefix}_connection_available",
             param_labels: %i[type provider]
           },
           time_to_ready_state: {
@@ -202,7 +297,6 @@ module Vmpooler
             torun: %i[manager],
             buckets: POOLER_READY_TIME_BUCKETS,
             docstring: 'Time taken for machine to read ready state for pool',
-            prom_metric_prefix: "#{@metrics_prefix}_time_to_ready_state",
             param_labels: %i[poolname]
           },
           migrate: {
@@ -210,7 +304,6 @@ module Vmpooler
             torun: %i[manager],
             buckets: POOLER_CLONE_TIME_BUCKETS,
             docstring: 'vmpooler time taken to migrate machine for pool',
-            prom_metric_prefix: "#{@metrics_prefix}_migrate",
             param_labels: %i[poolname]
           },
           clone: {
@@ -218,7 +311,6 @@ module Vmpooler
             torun: %i[manager],
             buckets: POOLER_CLONE_TIME_BUCKETS,
             docstring: 'vmpooler time taken to clone machine',
-            prom_metric_prefix: "#{@metrics_prefix}_clone",
             param_labels: %i[poolname]
           },
           destroy: {
@@ -226,7 +318,6 @@ module Vmpooler
             torun: %i[manager],
             buckets: POOLER_CLONE_TIME_BUCKETS,
             docstring: 'vmpooler time taken to destroy machine',
-            prom_metric_prefix: "#{@metrics_prefix}_destroy",
             param_labels: %i[poolname]
           },
           connection_waited: {
@@ -234,7 +325,6 @@ module Vmpooler
             torun: %i[manager],
             buckets: REDIS_CONNECT_BUCKETS,
             docstring: 'vmpooler redis connection wait time',
-            prom_metric_prefix: "#{@metrics_prefix}_connection_waited",
             param_labels: %i[type provider]
           }
         }
@@ -279,7 +369,7 @@ module Vmpooler
 
       def setup_prometheus_metrics(torun)
         @p_metrics = vmpooler_metrics_table
-        @p_metrics.each do |_name, metric_spec|
+        @p_metrics.each do |name, metric_spec|
           # Only register metrics appropriate to api or manager
           next if (torun & metric_spec[:torun]).empty?
 
@@ -288,7 +378,7 @@ module Vmpooler
             metric_spec[:metric_suffixes].each do |metric_suffix|
               add_prometheus_metric(
                 metric_spec,
-                "#{metric_spec[:prom_metric_prefix]}_#{metric_suffix[0]}",
+                "#{@prometheus_prefix}_#{name}_#{metric_suffix[0]}",
                 "#{metric_spec[:docstring]} #{metric_suffix[1]}"
               )
             end
@@ -296,7 +386,7 @@ module Vmpooler
             # No Additional counter suffixes so register this as metric.
             add_prometheus_metric(
               metric_spec,
-              metric_spec[:prom_metric_prefix],
+              "#{@prometheus_prefix}_#{name}",
               metric_spec[:docstring]
             )
           end
@@ -315,9 +405,9 @@ module Vmpooler
           metric_subkey = sublabels.shift.to_sym
           raise("Invalid Metric #{metric_key}_#{metric_subkey} for #{label}") unless metric[:metric_suffixes].key? metric_subkey.to_sym
 
-          metric[:metric_name] = "#{metric[:prom_metric_prefix]}_#{metric_subkey}"
+          metric[:metric_name] = "#{@prometheus_prefix}_#{metric_key}_#{metric_subkey}"
         else
-          metric[:metric_name] = metric[:prom_metric_prefix]
+          metric[:metric_name] = "#{@prometheus_prefix}_#{metric_key}"
         end
 
         # Check if we are looking for a parameter value at last element.
diff --git a/lib/vmpooler/metrics/promstats/collector_middleware.rb b/lib/vmpooler/metrics/promstats/collector_middleware.rb
index bfaa7a0..540b1e6 100644
--- a/lib/vmpooler/metrics/promstats/collector_middleware.rb
+++ b/lib/vmpooler/metrics/promstats/collector_middleware.rb
@@ -114,6 +114,9 @@ module Vmpooler
           path
             .gsub(%r{/vm/.+$}, '/vm')
             .gsub(%r{/ondemand/.+$}, '/ondemand')
+            .gsub(%r{/token/.+$}, '/token')
+            .gsub(%r{/lib/.+$}, '/lib')
+            .gsub(%r{/img/.+$}, '/img')
         end
       end
     end
diff --git a/lib/vmpooler/pool_manager.rb b/lib/vmpooler/pool_manager.rb
index 2380c36..95927d4 100644
--- a/lib/vmpooler/pool_manager.rb
+++ b/lib/vmpooler/pool_manager.rb
@@ -368,7 +368,7 @@ module Vmpooler
           $metrics.increment("errors.duplicatehostname.#{pool_name}")
           $logger.log('s', "[!] [#{pool_name}] Generated hostname #{hostname} was not unique (attempt \##{hostname_retries} of #{max_hostname_retries})")
         elsif !dns_available
-          $metrics.increment("errors.staledns.#{hostname}")
+          $metrics.increment("errors.staledns.#{pool_name}")
           $logger.log('s', "[!] [#{pool_name}] Generated hostname #{hostname} already exists in DNS records (#{dns_ip}), stale DNS")
         end
       end
@@ -539,15 +539,14 @@ module Vmpooler
     def purge_unused_vms_and_folders
       global_purge = $config[:config]['purge_unconfigured_folders']
       providers = $config[:providers].keys
-      providers.each do |provider|
-        provider_purge = $config[:providers][provider]['purge_unconfigured_folders']
-        provider_purge = global_purge if provider_purge.nil?
+      providers.each do |provider_key|
+        provider_purge = $config[:providers][provider_key]['purge_unconfigured_folders'] || global_purge
         if provider_purge
           Thread.new do
             begin
-              purge_vms_and_folders($providers[provider.to_s])
+              purge_vms_and_folders(provider_key)
             rescue StandardError => e
-              $logger.log('s', "[!] failed while purging provider #{provider} VMs and folders with an error: #{e}")
+              $logger.log('s', "[!] failed while purging provider #{provider_key} VMs and folders with an error: #{e}")
             end
           end
         end
@@ -556,14 +555,13 @@ module Vmpooler
     end
 
     # Return a list of pool folders
-    def pool_folders(provider)
-      provider_name = provider.name
+    def pool_folders(provider_name)
       folders = {}
       $config[:pools].each do |pool|
-        next unless pool['provider'] == provider_name
+        next unless pool['provider'] == provider_name.to_s
 
         folder_parts = pool['folder'].split('/')
-        datacenter = provider.get_target_datacenter_from_config(pool['name'])
+        datacenter = $providers[provider_name.to_s].get_target_datacenter_from_config(pool['name'])
         folders[folder_parts.pop] = "#{datacenter}/vm/#{folder_parts.join('/')}"
       end
       folders
@@ -577,8 +575,9 @@ module Vmpooler
       base.uniq
     end
 
-    def purge_vms_and_folders(provider)
-      configured_folders = pool_folders(provider)
+    def purge_vms_and_folders(provider_name)
+      provider = $providers[provider_name.to_s]
+      configured_folders = pool_folders(provider_name)
       base_folders = get_base_folders(configured_folders)
       whitelist = provider.provider_config['folder_whitelist']
       provider.purge_unconfigured_folders(base_folders, configured_folders, whitelist)
diff --git a/lib/vmpooler/version.rb b/lib/vmpooler/version.rb
index 2aced2c..7d40410 100644
--- a/lib/vmpooler/version.rb
+++ b/lib/vmpooler/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module Vmpooler
-  VERSION = '0.14.1'
+  VERSION = '0.14.5'
 end
diff --git a/spec/integration/api/v1/ondemandvm_spec.rb b/spec/integration/api/v1/ondemandvm_spec.rb
index 37b315c..a361f9f 100644
--- a/spec/integration/api/v1/ondemandvm_spec.rb
+++ b/spec/integration/api/v1/ondemandvm_spec.rb
@@ -24,15 +24,19 @@ describe Vmpooler::API::V1 do
           'vm_lifetime_auth' => 2,
           'max_ondemand_instances_per_request' => 50,
           'backend_weight' => {
-            'compute1' => 5
+            'compute1' => 5,
+            'compute2' => 0
           }
         },
         pools: [
-          {'name' => 'pool1', 'size' => 0},
-          {'name' => 'pool2', 'size' => 0, 'clone_target' => 'compute1'},
+          {'name' => 'pool1', 'size' => 0, 'clone_target' => 'compute1'},
+          {'name' => 'pool2', 'size' => 0, 'clone_target' => 'compute2'},
           {'name' => 'pool3', 'size' => 0, 'clone_target' => 'compute1'}
         ],
-        alias: { 'poolone' => ['pool1'] },
+        alias: {
+          'poolone' => ['pool1'],
+          'pool2' => ['pool1']
+        },
         pool_names: [ 'pool1', 'pool2', 'pool3', 'poolone' ]
       }
     }
@@ -92,6 +96,22 @@ describe Vmpooler::API::V1 do
             post "#{prefix}/ondemandvm", '{"poolone":"1"}'
           end
 
+          context 'with a backend of 0 weight' do
+            before(:each) do
+              config[:config]['backend_weight']['compute1'] = 0
+            end
+
+            it 'sets the platform string in redis for the request to indicate the selected platforms' do
+              expect(redis).to receive(:hset).with("vmpooler__odrequest__#{uuid}", 'requested', 'pool1:pool1:1')
+              post "#{prefix}/ondemandvm", '{"pool1":"1"}'
+            end
+          end
+
+          it 'sets the platform string in redis for the request to indicate the selected platforms using weight' do
+            expect(redis).to receive(:hset).with("vmpooler__odrequest__#{uuid}", 'requested', 'pool2:pool1:1')
+            post "#{prefix}/ondemandvm", '{"pool2":"1"}'
+          end
+
           context 'with domain set in the config' do
             let(:domain) { 'example.com' }
             before(:each) do
diff --git a/spec/unit/collector_middleware_spec.rb b/spec/unit/collector_middleware_spec.rb
index 671e118..5244c25 100644
--- a/spec/unit/collector_middleware_spec.rb
+++ b/spec/unit/collector_middleware_spec.rb
@@ -55,7 +55,7 @@ describe Vmpooler::Metrics::Promstats::CollectorMiddleware do
     expect(registry.get(metric).get(labels: labels)).to include("0.1" => 0, "0.25" => 1)
   end
 
-  it 'normalizes paths cotaining /vm by default' do
+  it 'normalizes paths containing /vm by default' do
     expect(Benchmark).to receive(:realtime).and_yield.and_return(0.3)
 
     get '/foo/vm/bar-mumble-flame'
@@ -83,6 +83,62 @@ describe Vmpooler::Metrics::Promstats::CollectorMiddleware do
     expect(registry.get(metric).get(labels: labels)).to include("0.1" => 0, "0.5" => 1)
   end
 
+  it 'normalizes paths containing /token by default' do
+    expect(Benchmark).to receive(:realtime).and_yield.and_return(0.3)
+
+    get '/token/secret-token-name'
+
+    metric = :http_server_requests_total
+    labels = { method: 'get', path: '/token', code: '200' }
+    expect(registry.get(metric).get(labels: labels)).to eql(1.0)
+
+    metric = :http_server_request_duration_seconds
+    labels = { method: 'get', path: '/token' }
+    expect(registry.get(metric).get(labels: labels)).to include("0.1" => 0, "0.5" => 1)
+  end
+
+  it 'normalizes paths containing /api/v1/token by default' do
+    expect(Benchmark).to receive(:realtime).and_yield.and_return(0.3)
+
+    get '/api/v1/token/secret-token-name'
+
+    metric = :http_server_requests_total
+    labels = { method: 'get', path: '/api/v1/token', code: '200' }
+    expect(registry.get(metric).get(labels: labels)).to eql(1.0)
+
+    metric = :http_server_request_duration_seconds
+    labels = { method: 'get', path: '/api/v1/token' }
+    expect(registry.get(metric).get(labels: labels)).to include("0.1" => 0, "0.5" => 1)
+  end
+
+  it 'normalizes paths containing /img by default' do
+    expect(Benchmark).to receive(:realtime).and_yield.and_return(0.3)
+
+    get '/img/image-name'
+
+    metric = :http_server_requests_total
+    labels = { method: 'get', path: '/img', code: '200' }
+    expect(registry.get(metric).get(labels: labels)).to eql(1.0)
+
+    metric = :http_server_request_duration_seconds
+    labels = { method: 'get', path: '/img' }
+    expect(registry.get(metric).get(labels: labels)).to include("0.1" => 0, "0.5" => 1)
+  end
+
+  it 'normalizes paths containing /lib by default' do
+    expect(Benchmark).to receive(:realtime).and_yield.and_return(0.3)
+
+    get '/lib/xxxxx.js'
+
+    metric = :http_server_requests_total
+    labels = { method: 'get', path: '/lib', code: '200' }
+    expect(registry.get(metric).get(labels: labels)).to eql(1.0)
+
+    metric = :http_server_request_duration_seconds
+    labels = { method: 'get', path: '/lib' }
+    expect(registry.get(metric).get(labels: labels)).to include("0.1" => 0, "0.5" => 1)
+  end
+
   context 'when the app raises an exception' do
     let(:original_app) do
       lambda do |env|
diff --git a/spec/unit/pool_manager_spec.rb b/spec/unit/pool_manager_spec.rb
index 446d1ba..e8a17a1 100644
--- a/spec/unit/pool_manager_spec.rb
+++ b/spec/unit/pool_manager_spec.rb
@@ -913,7 +913,7 @@ EOT
         resolv = class_double("Resolv").as_stubbed_const(:transfer_nested_constants => true)
         expect(subject).to receive(:generate_and_check_hostname).exactly(3).times.and_return([vm_name, true]) #skip this, make it available all times
         expect(resolv).to receive(:getaddress).exactly(3).times.and_return("1.2.3.4")
-        expect(metrics).to receive(:increment).with("errors.staledns.#{vm_name}").exactly(3).times
+        expect(metrics).to receive(:increment).with("errors.staledns.#{pool}").exactly(3).times
         expect{subject._clone_vm(pool,provider)}.to raise_error(/Unable to generate a unique hostname after/)
       end
       it 'should be successful if DNS does not exist' do
@@ -1418,16 +1418,24 @@ EOT
       )
     }
 
-    it 'should return a list of pool folders' do
-      expect(provider).to receive(:get_target_datacenter_from_config).with(pool).and_return(datacenter)
+    context 'when evaluating pool folders' do
+      before do
+        expect(subject).not_to be_nil
+        # Inject mock provider into global variable - Note this is a code smell
+        $providers = { provider_name => provider }
+      end
 
-      expect(subject.pool_folders(provider)).to eq(expected_response)
-    end
+      it 'should return a list of pool folders' do
+        expect(provider).to receive(:get_target_datacenter_from_config).with(pool).and_return(datacenter)
 
-    it 'should raise an error when the provider fails to get the datacenter' do
-      expect(provider).to receive(:get_target_datacenter_from_config).with(pool).and_raise('mockerror')
+        expect(subject.pool_folders(provider_name)).to eq(expected_response)
+      end
 
-      expect{ subject.pool_folders(provider) }.to raise_error(RuntimeError, 'mockerror')
+      it 'should raise an error when the provider fails to get the datacenter' do
+        expect(provider).to receive(:get_target_datacenter_from_config).with(pool).and_raise('mockerror')
+
+        expect{ subject.pool_folders(provider_name) }.to raise_error(RuntimeError, 'mockerror')
+      end
     end
   end
 
@@ -1456,20 +1464,28 @@ EOT
       )
     }
 
-    it 'should run purge_unconfigured_folders' do
-      expect(subject).to receive(:pool_folders).and_return(configured_folders)
-      expect(provider).to receive(:purge_unconfigured_folders).with(base_folders, configured_folders, whitelist)
-      expect(provider).to receive(:provider_config).and_return({})
+    context 'when purging folders' do
+      before do
+        expect(subject).not_to be_nil
+        # Inject mock provider into global variable - Note this is a code smell
+        $providers = { provider_name => provider }
+      end
 
-      subject.purge_vms_and_folders(provider)
-    end
+      it 'should run purge_unconfigured_folders' do
+        expect(subject).to receive(:pool_folders).and_return(configured_folders)
+        expect(provider).to receive(:purge_unconfigured_folders).with(base_folders, configured_folders, whitelist)
+        expect(provider).to receive(:provider_config).and_return({})
 
-    it 'should raise any errors' do
-      expect(subject).to receive(:pool_folders).and_return(configured_folders)
-      expect(provider).to receive(:purge_unconfigured_folders).with(base_folders, configured_folders, whitelist).and_raise('mockerror')
-      expect(provider).to receive(:provider_config).and_return({})
+        subject.purge_vms_and_folders(provider_name)
+      end
 
-      expect{ subject.purge_vms_and_folders(provider) }.to raise_error(RuntimeError, 'mockerror')
+      it 'should raise any errors' do
+        expect(subject).to receive(:pool_folders).and_return(configured_folders)
+        expect(provider).to receive(:purge_unconfigured_folders).with(base_folders, configured_folders, whitelist).and_raise('mockerror')
+        expect(provider).to receive(:provider_config).and_return({})
+
+        expect{ subject.purge_vms_and_folders(provider_name) }.to raise_error(RuntimeError, 'mockerror')
+      end
     end
   end
 
diff --git a/spec/unit/promstats_spec.rb b/spec/unit/promstats_spec.rb
index eb66c5f..909b437 100644
--- a/spec/unit/promstats_spec.rb
+++ b/spec/unit/promstats_spec.rb
@@ -4,7 +4,7 @@ require 'spec_helper'
 
 describe 'prometheus' do
   logger = MockLogger.new
-  params = { 'prefix': 'test', 'metrics_prefix': 'mtest', 'endpoint': 'eptest' }
+  params = { 'prefix' => 'test', 'prometheus_prefix'  => 'mtest', 'prometheus_endpoint'  => 'eptest' }
   subject = Vmpooler::Metrics::Promstats.new(logger, params)
   let(:logger) { MockLogger.new }
 
@@ -24,7 +24,7 @@ describe 'prometheus' do
       before { subject.instance_variable_set(:@p_metrics, { foo: foo_metrics }) }
   
       it 'returns the metric for a given label including parsed labels' do
-        expect(subject.find_metric('foo.bar')).to include(metric_name: '_bar')
+        expect(subject.find_metric('foo.bar')).to include(metric_name: 'mtest_foo_bar')
         expect(subject.find_metric('foo.bar')).to include(foo_metrics)
         expect(subject.find_metric('foo.bar')).to include(labels_hash)
       end
@@ -57,7 +57,6 @@ describe 'prometheus' do
       Prometheus::Client.config.data_store = Prometheus::Client::DataStores::Synchronized.new
       subject.setup_prometheus_metrics(%i[api manager])
     end
-    let(:MCOUNTER) { 1 }
 
     describe '#setup_prometheus_metrics' do
       it 'calls add_prometheus_metric for each item in list' do
@@ -260,12 +259,12 @@ describe 'prometheus' do
           po.get(labels: metric[:labels])
         }.by(1)
       end
-      it 'Increments label api_vm.#{method}.#{subpath}.#{operation}' do
+      it 'Increments label http_requests_vm_total.#{method}.#{subpath}.#{operation}' do
         method = 'get'
         subpath = 'template'
         operation = 'something'
-        expect { subject.increment("api_vm.#{method}.#{subpath}.#{operation}") }.to change {
-          metric, po = subject.get("api_vm.#{method}.#{subpath}.#{operation}")
+        expect { subject.increment("http_requests_vm_total.#{method}.#{subpath}.#{operation}") }.to change {
+          metric, po = subject.get("http_requests_vm_total.#{method}.#{subpath}.#{operation}")
           po.get(labels: metric[:labels])
         }.by(1)
       end
diff --git a/vmpooler.yaml.example b/vmpooler.yaml.example
index 6120c50..cd53faf 100644
--- a/vmpooler.yaml.example
+++ b/vmpooler.yaml.example
@@ -240,7 +240,7 @@
 #
 # This section contains the connection information required to store
 # historical data via statsd.  This is mutually exclusive with graphite
-# and takes precedence.
+# and prometheus and takes precedence.
 #
 # Available configuration parameters:
 #
@@ -267,7 +267,7 @@
 #
 # This section contains the connection information required to store
 # historical data in an external Graphite database.  This is mutually exclusive
-# with statsd.
+# with statsd and prometheus - i.e. only one can be selected.
 #
 # Available configuration parameters:
 #
@@ -288,6 +288,34 @@
 :graphite:
   server: 'graphite.example.com'
 
+# :prometheus
+#
+# This section contains the connection information required to store
+# historical data in an external Graphite database.  This is mutually exclusive
+# with statsd and graphite - i.e. only one can be selected.
+#
+# Available configuration parameters:
+#
+#   - prefix
+#     The prefix for this vmpooler instance.
+#     (optional; default: 'vmpooler')
+#
+#   - prometheus_prefix
+#     The prefix to use while storing prometheus data.
+#     (optional; default: 'vmpooler')
+#
+#   - prometheus_endpoint
+#     The metrics endpoint on the vmpooler server
+#     (optional; default: '/prometheus')
+
+# Example:
+
+:prometheus:
+  prefix: 'staging'
+  prometheus_prefix: 'vmpooler'
+  prometheus_endpoint: '/prometheus'
+
+
 # :auth:
 #
 # This section contains information related to authenticating users