diff --git a/devops-service/app/api2/handlers/server.rb b/devops-service/app/api2/handlers/server.rb
index 6eb4cbd..bd27bf8 100644
--- a/devops-service/app/api2/handlers/server.rb
+++ b/devops-service/app/api2/handlers/server.rb
@@ -79,12 +79,14 @@ module Devops
         end
 
         def pause_server node_name
-          s = Server.get_server_by_key(node_name, parser.instance_key)
+          s = get_server_by_key(node_name, parser.instance_key)
           ## Authorization
           Devops::Db.connector.check_project_auth s.project, s.deploy_env, parser.current_user
           provider = s.provider_instance
           r = provider.pause_server s
           if r.nil?
+            set_last_operation_type_and_save(s, Devops::Model::Server::OperationType::PAUSE)
+
             "Server with instance ID '#{s.id}' and node name '#{node_name}' is paused"
           else
             raise ConflictException.new("Server with instance ID '#{s.id}' and node name '#{node_name}' can not be paused, It in state '#{r}'", 409)
@@ -92,12 +94,14 @@ module Devops
         end
 
         def unpause_server node_name
-          s = Server.get_server_by_key(node_name, parser.instance_key)
+          s = get_server_by_key(node_name, parser.instance_key)
            ## Authorization
           Devops::Db.connector.check_project_auth s.project, s.deploy_env, parser.current_user
           provider = s.provider_instance
           r = provider.unpause_server s
           if r.nil?
+            set_last_operation_type_and_save(s, Devops::Model::Server::OperationType::UNPAUSE)
+
             "Server with instance ID '#{s.id}' and node name '#{node_name}' is unpaused"
           else
             raise ConflictException.new("Server with instance ID '#{s.id}' and node name '#{node_name}' can not be unpaused, It in state '#{r}'")
@@ -110,7 +114,7 @@ module Devops
           Devops::Db.connector.check_project_auth s.project, s.deploy_env, user
           raise ConflictException.new("Server '#{node_name}' already reserved") unless s.reserved_by.nil?
           s.reserved_by = user
-          Devops::Db.connector.server_update(s)
+          set_last_operation_type_and_save(s, Devops::Model::Server::OperationType::RESERVE)
         end
 
         def unreserve_server node_name
@@ -118,7 +122,7 @@ module Devops
           Devops::Db.connector.check_project_auth s.project, s.deploy_env, parser.current_user
           raise ConflictException.new("Server '#{node_name}' is not reserved") if s.reserved_by.nil?
           s.reserved_by = nil
-          Devops::Db.connector.server_update(s)
+          set_last_operation_type_and_save(s, Devops::Model::Server::OperationType::UNRESERVE)
         end
 
         # TODO: check bootstrap template name
@@ -284,6 +288,11 @@ module Devops
           end
         end
 
+        def set_last_operation_type_and_save(server, operation_type)
+          server.set_last_operation(operation_type)
+          Devops::Db.connector.server_update(server)
+        end
+
       end
     end
   end
diff --git a/devops-service/db/mongo/connectors/server.rb b/devops-service/db/mongo/connectors/server.rb
index 4ab4fea..12f9e2a 100644
--- a/devops-service/db/mongo/connectors/server.rb
+++ b/devops-service/db/mongo/connectors/server.rb
@@ -63,17 +63,14 @@ module Connectors
     end
 
     def server_insert(server)
-      #server.validate!
       server.created_at = Time.now
       collection.insert(server.to_mongo_hash)
     end
 
-    # somewhy servers are not validated in previous version of code. I leave this until I know, why.
     def server_update(server)
       collection.update({'_id' => server.id}, server.to_hash_without_id)
     end
 
-    # somewhy servers are not validated in previous version of code. I leave this until I know, why.
     def server_set_chef_node_name(server)
       collection.update({'_id' => server.id}, {'$set' => {'chef_node_name' => server.chef_node_name}})
     end
diff --git a/devops-service/db/mongo/models/server.rb b/devops-service/db/mongo/models/server.rb
index c9fc4f9..91ec775 100644
--- a/devops-service/db/mongo/models/server.rb
+++ b/devops-service/db/mongo/models/server.rb
@@ -9,8 +9,17 @@ module Devops
 
       include ModelWithProvider
 
+      module OperationType
+        CREATION = :creation
+        DEPLOY = :deploy
+        RESERVE = :reserve
+        UNRESERVE = :unreserve
+        PAUSE = :pause
+        UNPAUSE = :unpause
+      end
+
       attr_accessor :chef_node_name, :id, :remote_user, :project, :deploy_env, :private_ip, :public_ip, :created_at, :without_bootstrap, :created_by, :reserved_by, :stack, :run_list
-      attr_accessor :key
+      attr_accessor :key, :last_operation_at, :last_operation_type
 
       types :id => {:type => String, :empty => false},
             :provider => {:type => String, :empty => false},
@@ -29,7 +38,8 @@ module Devops
       set_validators  ::Validators::DeployEnv::RunList
 
       def self.fields
-        ["chef_node_name", "project", "deploy_env", "provider", "remote_user", "private_ip", "public_ip", "created_at", "created_by", "key", "reserved_by", "run_list", "stack"]
+        ["chef_node_name", "project", "deploy_env", "provider", "remote_user", "private_ip", "public_ip", "created_at", "created_by", "key", "reserved_by", "run_list", "stack",
+          "last_operation_type", "last_operation_at"]
       end
 
       def initialize s={}
@@ -47,6 +57,8 @@ module Devops
         self.reserved_by = s["reserved_by"]
         self.stack = s["stack"]
         self.run_list = s["run_list"] || []
+        self.last_operation_at = s["last_operation_at"]
+        self.last_operation_type = s["last_operation_type"]
         self
       end
 
@@ -77,7 +89,9 @@ module Devops
           "key" => self.key,
           "reserved_by" => self.reserved_by,
           "stack" => stack,
-          "run_list" => self.run_list
+          "run_list" => self.run_list,
+          "last_operation_at" => self.last_operation_at,
+          "last_operation_type" => self.last_operation_type
         }.merge(provider_hash).delete_if { |k,v| v.nil? }
       end
 
@@ -100,6 +114,11 @@ module Devops
         self.provider == Provider::Static::PROVIDER
       end
 
+      def set_last_operation(operation_type)
+        self.last_operation_type = operation_type
+        self.last_operation_at = Time.now
+      end
+
     end
   end
 end
diff --git a/devops-service/db/validators/all.rb b/devops-service/db/validators/all.rb
index 37f2e28..dc27475 100644
--- a/devops-service/db/validators/all.rb
+++ b/devops-service/db/validators/all.rb
@@ -12,5 +12,5 @@ require "db/validators/base"
   'db/validators/key/*.rb',
   'db/validators/image/*.rb'
 ].each do |files_regexp|
-  Dir[files_regexp].each {|file| require file }
+  Dir[File.join(Devops::Application.root, files_regexp)].each {|file| require file }
 end
diff --git a/devops-service/lib/executors/server_executor.rb b/devops-service/lib/executors/server_executor.rb
index d53539d..886d399 100644
--- a/devops-service/lib/executors/server_executor.rb
+++ b/devops-service/lib/executors/server_executor.rb
@@ -76,6 +76,7 @@ module Devops
 
       def create_server options
         @server = Devops::Model::Server.new({"project" => @project.id, "deploy_env" => @deploy_env.identifier, "created_by" => options["created_by"], "provider" => @deploy_env.provider, "provider_account" => @deploy_env.provider_account})
+        @server.set_last_operation(Devops::Model::Server::OperationType::CREATION)
         provider = @deploy_env.provider_instance
         mongo = ::Devops::Db.connector
         begin
@@ -378,6 +379,10 @@ module Devops
           @out << "\nAfter deploy hooks...\n"
           res = self.run_hook(:after_deploy, @out, deploy_info)
           @out << "Done\n"
+
+          @server.set_last_operation(Devops::Model::Server::OperationType::DEPLOY)
+          Devops::Db.connector.server_update(@server)
+
           0
         end
       end