diff --git a/TODO.md b/TODO.md
index f817d34b..0f93df6a 100644
--- a/TODO.md
+++ b/TODO.md
@@ -48,5 +48,4 @@ Remember that, as always with QuerySets, any subsequent chained methods which im
 * passlib; nano /usr/local/lib/python2.7/dist-packages/passlib/ext/django/utils.py SortedDict -> collections.OrderedDict
 * pip install pyinotify
 
-
-* Backend.operations dynamically generated based on defined methods
+* create custom field that returns backend python objects
diff --git a/orchestra/apps/accounts/admin.py b/orchestra/apps/accounts/admin.py
index cce56fc6..ad315953 100644
--- a/orchestra/apps/accounts/admin.py
+++ b/orchestra/apps/accounts/admin.py
@@ -71,6 +71,8 @@ class AccountAdmin(ExtendedModelAdmin):
     
     def save_model(self, request, obj, form, change):
         """ Save user and account, they are interdependent """
+        if change:
+            return super(AccountAdmin, self).save_model(request, obj, form, change)
         obj.user.save()
         obj.user_id = obj.user.pk
         obj.save()
diff --git a/orchestra/apps/domains/api.py b/orchestra/apps/domains/api.py
index b5089bec..e4e62045 100644
--- a/orchestra/apps/domains/api.py
+++ b/orchestra/apps/domains/api.py
@@ -22,7 +22,9 @@ class DomainViewSet(AccountApiMixin, viewsets.ModelViewSet):
     @link()
     def view_zone(self, request, pk=None):
         domain = self.get_object()
-        return Response({'zone': domain.render_zone()})
+        return Response({
+            'zone': domain.render_zone()
+        })
     
     def metadata(self, request):
         ret = super(DomainViewSet, self).metadata(request)
diff --git a/orchestra/apps/orchestration/backends.py b/orchestra/apps/orchestration/backends.py
index 70f97b88..d6c52cf0 100644
--- a/orchestra/apps/orchestration/backends.py
+++ b/orchestra/apps/orchestration/backends.py
@@ -69,7 +69,7 @@ class ServiceBackend(object):
     
     @classmethod
     def get_backend(cls, name):
-        for backend in ServiceMonitor.get_backends():
+        for backend in ServiceBackend.get_backends():
             if backend.get_name() == name:
                 return backend
         raise KeyError('This backend is not registered')
diff --git a/orchestra/apps/orchestration/helpers.py b/orchestra/apps/orchestration/helpers.py
index 6196e4e8..c0cf370c 100644
--- a/orchestra/apps/orchestration/helpers.py
+++ b/orchestra/apps/orchestration/helpers.py
@@ -38,7 +38,7 @@ def message_user(request, logs):
     errors = total-successes
     if errors:
         msg = 'backends have' if errors > 1 else 'backend has'
-        msg = _("%d out of %d {0} fail to executed".format(msg))
+        msg = _("%d out of %d {0} fail to execute".format(msg))
         messages.warning(request, msg % (errors, total))
     else:
         msg = 'backends have' if successes > 1 else 'backend has'
diff --git a/orchestra/apps/orchestration/methods.py b/orchestra/apps/orchestration/methods.py
index 8ac97a80..2ca95b7a 100644
--- a/orchestra/apps/orchestration/methods.py
+++ b/orchestra/apps/orchestration/methods.py
@@ -40,12 +40,12 @@ def BashSSH(backend, log, server, cmds):
         channel = transport.open_session()
         
         sftp = paramiko.SFTPClient.from_transport(transport)
-        sftp.put(path, path)
+        sftp.put(path, "%s.remote" % path)
         sftp.close()
         os.remove(path)
         
         context = {
-            'path': path,
+            'path': "%s.remote" % path,
             'digest': digest
         }
         cmd = (
diff --git a/orchestra/apps/orchestration/models.py b/orchestra/apps/orchestration/models.py
index e2468507..5f3fad8c 100644
--- a/orchestra/apps/orchestration/models.py
+++ b/orchestra/apps/orchestration/models.py
@@ -4,6 +4,7 @@ from django.core.exceptions import ValidationError
 from django.db import models
 from django.utils.translation import ugettext_lazy as _
 
+from orchestra.models.fields import NullableCharField
 from orchestra.utils.apps import autodiscover
 from orchestra.utils.functional import cached
 
@@ -14,9 +15,8 @@ from .backends import ServiceBackend
 class Server(models.Model):
     """ Machine runing daemons (services) """
     name = models.CharField(_("name"), max_length=256, unique=True)
-    # TODO unique address with blank=True (nullablecharfield)
-    address = models.CharField(_("address"), max_length=256, blank=True,
-            help_text=_("IP address or domain name"))
+    address = NullableCharField(_("address"), max_length=256, blank=True,
+            null=True, unique=True, help_text=_("IP address or domain name"))
     description = models.TextField(_("description"), blank=True)
     os = models.CharField(_("operative system"), max_length=32,
             choices=settings.ORCHESTRATION_OS_CHOICES,
@@ -82,8 +82,7 @@ class BackendOperation(models.Model):
     MONITOR = 'monitor'
     
     log = models.ForeignKey('orchestration.BackendLog', related_name='operations')
-    # TODO backend and backend_class() (like content_type)
-    backend_class = models.CharField(_("backend"), max_length=256)
+    backend = models.CharField(_("backend"), max_length=256)
     action = models.CharField(_("action"), max_length=64)
     content_type = models.ForeignKey(ContentType)
     object_id = models.PositiveIntegerField()
@@ -94,11 +93,11 @@ class BackendOperation(models.Model):
         verbose_name_plural = _("Operations")
     
     def __unicode__(self):
-        return '%s.%s(%s)' % (self.backend_class, self.action, self.instance)
+        return '%s.%s(%s)' % (self.backend, self.action, self.instance)
     
     def __hash__(self):
         """ set() """
-        backend = getattr(self, 'backend', self.backend_class)
+        backend = getattr(self, 'backend', self.backend)
         return hash(backend) + hash(self.instance) + hash(self.action)
     
     def __eq__(self, operation):
@@ -107,13 +106,16 @@ class BackendOperation(models.Model):
     
     @classmethod
     def create(cls, backend, instance, action):
-        op = cls(backend_class=backend.get_name(), instance=instance, action=action)
+        op = cls(backend=backend.get_name(), instance=instance, action=action)
         op.backend = backend
         return op
     
     @classmethod
     def execute(cls, operations):
         return manager.execute(operations)
+    
+    def backend_class(self):
+        return ServiceBackend.get_backend(self.backend)
 
 
 autodiscover('backends')
diff --git a/orchestra/apps/resources/admin.py b/orchestra/apps/resources/admin.py
index 48ed4217..f714b062 100644
--- a/orchestra/apps/resources/admin.py
+++ b/orchestra/apps/resources/admin.py
@@ -1,8 +1,9 @@
-from django.contrib import admin
+from django.contrib import admin, messages
 from django.contrib.contenttypes import generic
 from django.utils.functional import cached_property
 from django.utils.translation import ugettext_lazy as _
 
+from orchestra.admin import ExtendedModelAdmin
 from orchestra.admin.filters import UsedContentTypeFilter
 from orchestra.admin.utils import insertattr, get_modeladmin
 from orchestra.core import services
@@ -12,14 +13,34 @@ from .forms import ResourceForm
 from .models import Resource, ResourceData, MonitorData
 
 
-class ResourceAdmin(admin.ModelAdmin):
-    # TODO warning message server/celery should be restarted when creating things
-    
+class ResourceAdmin(ExtendedModelAdmin):
     list_display = (
         'name', 'verbose_name', 'content_type', 'period', 'ondemand',
-        'default_allocation', 'disable_trigger'
+        'default_allocation', 'disable_trigger', 'crontab',
     )
     list_filter = (UsedContentTypeFilter, 'period', 'ondemand', 'disable_trigger')
+    fieldsets = (
+        (None, {
+            'fields': ('name', 'content_type', 'period'),
+        }),
+        (_("Configuration"), {
+            'fields': ('verbose_name', 'default_allocation', 'ondemand',
+                       'disable_trigger', 'is_active'),
+        }),
+        (_("Monitoring"), {
+            'fields': ('monitors', 'crontab'),
+        }),
+    )
+    change_readonly_fields = ('name', 'content_type', 'period')
+    
+    def add_view(self, request, **kwargs):
+        """ Warning user if the node is not fully configured """
+        if request.method == 'GET':
+            messages.warning(request, _(
+                "Restarting orchestra and celery is required to fully apply changes. "
+                "Remember that allocated values will be applied when objects are saved"
+            ))
+        return super(ResourceAdmin, self).add_view(request, **kwargs)
     
     def save_model(self, request, obj, form, change):
         super(ResourceAdmin, self).save_model(request, obj, form, change)
diff --git a/orchestra/apps/resources/backends.py b/orchestra/apps/resources/backends.py
index 97a94582..0ba02c4f 100644
--- a/orchestra/apps/resources/backends.py
+++ b/orchestra/apps/resources/backends.py
@@ -1,4 +1,9 @@
+import datetime
+
+from django.contrib.contenttypes.models import ContentType
+
 from orchestra.apps.orchestration import ServiceBackend
+from orchestra.utils.functional import cached
 
 
 class ServiceMonitor(ServiceBackend):
@@ -14,14 +19,34 @@ class ServiceMonitor(ServiceBackend):
         """ filter monitor classes """
         return [plugin for plugin in cls.plugins if ServiceMonitor in plugin.__mro__]
     
-    def store(self, stdout):
+    @cached
+    def get_last_date(self, obj):
+        from .models import MonitorData
+        try:
+            # TODO replace
+            #return MonitorData.objects.filter(content_object=obj).latest().date
+            ct = ContentType.objects.get(app_label=obj._meta.app_label, model=obj._meta.model_name)
+            return MonitorData.objects.filter(content_type=ct, object_id=obj.pk).latest().date
+        except MonitorData.DoesNotExist:
+            return self.get_current_date() - datetime.timedelta(days=1)
+    
+    @cached
+    def get_current_date(self):
+        return datetime.datetime.now()
+    
+    def store(self, log):
         """ object_id value """
-        for line in stdout.readlines():
+        from .models import MonitorData
+        name = self.get_name()
+        app_label, model_name = self.model.split('.')
+        ct = ContentType.objects.get(app_label=app_label, model=model_name.lower())
+        for line in log.stdout.splitlines():
             line = line.strip()
             object_id, value = line.split()
-            # TODO date
-            MonitorHistory.store(self.model, object_id, value, date)
+            MonitorData.objects.create(monitor=name, object_id=object_id,
+                    content_type=ct, value=value, date=self.get_current_date())
     
     def execute(self, server):
-        log = super(MonitorBackend, self).execute(server)
+        log = super(ServiceMonitor, self).execute(server)
+        self.store(log)
         return log
diff --git a/orchestra/apps/resources/forms.py b/orchestra/apps/resources/forms.py
index 8bcd545c..fc46c8a4 100644
--- a/orchestra/apps/resources/forms.py
+++ b/orchestra/apps/resources/forms.py
@@ -21,7 +21,6 @@ class ResourceForm(forms.ModelForm):
         super(ResourceForm, self).__init__(*args, **kwargs)
         if self.resource:
             self.fields['verbose_name'].initial = self.resource.verbose_name
-            self.fields['used'].initial = self.resource.get_used() # TODO
             if self.resource.ondemand:
                 self.fields['allocated'].required = False
                 self.fields['allocated'].widget = ReadOnlyWidget(None, '')
diff --git a/orchestra/apps/resources/models.py b/orchestra/apps/resources/models.py
index c2a5a136..4cc85c7a 100644
--- a/orchestra/apps/resources/models.py
+++ b/orchestra/apps/resources/models.py
@@ -1,7 +1,7 @@
 import datetime
 
 from django.db import models
-from django.contrib.contenttypes import generic
+from django.contrib.contenttypes.fields import GenericForeignKey, GenericRelation
 from django.contrib.contenttypes.models import ContentType
 from django.core import validators
 from django.utils.translation import ugettext_lazy as _
@@ -34,17 +34,22 @@ class Resource(models.Model):
             validators=[validators.RegexValidator(r'^[a-z0-9_\-]+$',
                         _('Enter a valid name.'), 'invalid')])
     verbose_name = models.CharField(_("verbose name"), max_length=256, unique=True)
-    content_type = models.ForeignKey(ContentType) # TODO filter by servicE?
-    period = models.CharField(_("period"), max_length=16, choices=PERIODS,
-            default=LAST)
-    ondemand = models.BooleanField(_("on demand"), default=False)
+    content_type = models.ForeignKey(ContentType,
+            help_text=_("Model where this resource will be hooked"))
+    period = models.CharField(_("period"), max_length=16, choices=PERIODS, default=LAST,
+            help_text=_("Operation used for aggregating this resource monitored data."))
+    ondemand = models.BooleanField(_("on demand"), default=False,
+            help_text=_("If enabled the resource will not be pre-allocated, "
+                        "but allocated under the application demand"))
     default_allocation = models.PositiveIntegerField(_("default allocation"),
+            help_text=_("Default allocation value used when this is not an "
+                        "on demand resource"),
             null=True, blank=True)
     is_active = models.BooleanField(_("is active"), default=True)
-    disable_trigger = models.BooleanField(_("disable trigger"), default=False)
+    disable_trigger = models.BooleanField(_("disable trigger"), default=False,
+            help_text=_("Disables monitor's resource exeeded and recovery triggers"))
     crontab = models.ForeignKey(CrontabSchedule, verbose_name=_("crontab"),
             help_text=_("Crontab for periodic execution"))
-    # TODO create custom field that returns backend python objects
     monitors = MultiSelectField(_("monitors"), max_length=256,
             choices=ServiceMonitor.get_choices())
     
@@ -58,13 +63,16 @@ class Resource(models.Model):
         try:
             task = PeriodicTask.objects.get(name=name)
         except PeriodicTask.DoesNotExist:
-            PeriodicTask.objects.create(name=name, task='resources.Monitor',
-                                        args=[self.pk], crontab=self.crontab)
-        else: 
-            if task.crontab != self.crontab:
+            if self.is_active:
+                PeriodicTask.objects.create(name=name, task='resources.Monitor',
+                                            args=[self.pk], crontab=self.crontab)
+        else:
+            if not self.is_active:
+                task.delete()
+            elif task.crontab != self.crontab:
                 task.crontab = self.crontab
                 task.save()
-            
+    
     def delete(self, *args, **kwargs):
         super(Resource, self).delete(*args, **kwargs)
         name = 'monitor.%s' % str(self)
@@ -97,7 +105,7 @@ class ResourceData(models.Model):
     last_update = models.DateTimeField(null=True)
     allocated = models.PositiveIntegerField(null=True)
     
-    content_object = generic.GenericForeignKey()
+    content_object = GenericForeignKey()
     
     class Meta:
         unique_together = ('resource', 'content_type', 'object_id')
@@ -159,7 +167,7 @@ class MonitorData(models.Model):
     date = models.DateTimeField(auto_now_add=True)
     value = models.PositiveIntegerField()
     
-    content_object = generic.GenericForeignKey()
+    content_object = GenericForeignKey()
     
     class Meta:
         get_latest_by = 'date'
@@ -170,7 +178,7 @@ class MonitorData(models.Model):
 
 
 def create_resource_relation():
-    relation = generic.GenericRelation('resources.ResourceData')
+    relation = GenericRelation('resources.ResourceData')
     for resources in Resource.group_by_content_type():
         model = resources[0].content_type.model_class()
         model.add_to_class('resources', relation)
diff --git a/orchestra/apps/resources/serializers.py b/orchestra/apps/resources/serializers.py
index 0e391bc2..9cb36e8a 100644
--- a/orchestra/apps/resources/serializers.py
+++ b/orchestra/apps/resources/serializers.py
@@ -7,6 +7,9 @@ from .models import Resource, ResourceData
 
 
 class ResourceSerializer(serializers.ModelSerializer):
+    # TODO required allocation serializers (like resource form)
+    # TODO create missing ResourceData (like resource form)
+    # TODO make default allocation available on OPTIONS (like resource form)
     name = serializers.SerializerMethodField('get_name')
     
     class Meta:
diff --git a/orchestra/apps/users/roles/mail/backends.py b/orchestra/apps/users/roles/mail/backends.py
index 122f3cea..a892703c 100644
--- a/orchestra/apps/users/roles/mail/backends.py
+++ b/orchestra/apps/users/roles/mail/backends.py
@@ -12,6 +12,7 @@ from . import settings
 class MailSystemUserBackend(ServiceController):
     verbose_name = _("Mail system user")
     model = 'mail.Mailbox'
+    # TODO related_models = ('resources__content_type') ??
     
     DEFAULT_GROUP = 'postfix'
     
diff --git a/orchestra/apps/websites/backends/apache.py b/orchestra/apps/websites/backends/apache.py
index 2af75954..28107279 100644
--- a/orchestra/apps/websites/backends/apache.py
+++ b/orchestra/apps/websites/backends/apache.py
@@ -185,47 +185,48 @@ class Apache2Traffic(ServiceMonitor):
         context = self.get_context(site)
         self.append("""
             awk 'BEGIN {
-                ini = "%(start_date)s";
-                end = "%(end_date)s";
+                ini = "%(last_date)s";
+                end = "%(current_date)s";
                 
-                months["Jan"]="01";
-                months["Feb"]="02";
-                months["Mar"]="03";
-                months["Apr"]="04";
-                months["May"]="05";
-                months["Jun"]="06";
-                months["Jul"]="07";
-                months["Aug"]="08";
-                months["Sep"]="09";
-                months["Oct"]="10";
-                months["Nov"]="11";
-                months["Dec"]="12";
+                months["Jan"] = "01";
+                months["Feb"] = "02";
+                months["Mar"] = "03";
+                months["Apr"] = "04";
+                months["May"] = "05";
+                months["Jun"] = "06";
+                months["Jul"] = "07";
+                months["Aug"] = "08";
+                months["Sep"] = "09";
+                months["Oct"] = "10";
+                months["Nov"] = "11";
+                months["Dec"] = "12";
             } {
-                date = substr($4,2)
-                year = substr(date,8,4)
-                month = months[substr(date,4,3)];
-                day = substr(date,1,2)
-                hour = substr(date,13,2)
-                minute = substr(date,16,2)
-                second = substr(date,19,2);
+                date = substr($4, 2)
+                year = substr(date, 8, 4)
+                month = months[substr(date, 4, 3)];
+                day = substr(date, 1, 2)
+                hour = substr(date, 13, 2)
+                minute = substr(date, 16, 2)
+                second = substr(date, 19, 2);
                 line_date = year month day hour minute second
                 if ( line_date > ini && line_date < end)
                     if ( $10 == "" )
-                        sum+=$9
+                        sum += $9
                     else
-                        sum+=$10;
+                        sum += $10;
             } END {
                 print sum;
             }' %(log_file)s | {
                 read value
-                echo %(site_name)s $value
+                echo %(site_id)s $value
             }
             """ % context)
     
     def get_context(self, site):
+        # TODO log timezone!!
         return {
             'log_file': os.path.join(settings.WEBSITES_BASE_APACHE_LOGS, site.unique_name),
-            'start_date': '',
-            'end_date': '',
-            'site_name': '',
+            'last_date': self.get_last_date(site).strftime("%Y%m%d%H%M%S"),
+            'current_date': self.get_current_date().strftime("%Y%m%d%H%M%S"),
+            'site_id': site.pk,
         }
diff --git a/orchestra/models/fields.py b/orchestra/models/fields.py
index 88dffd23..9668ab6b 100644
--- a/orchestra/models/fields.py
+++ b/orchestra/models/fields.py
@@ -52,6 +52,12 @@ class MultiSelectField(models.CharField):
         return [ value for value,__ in arr_choices ]
 
 
+class NullableCharField(models.CharField):
+     def get_db_prep_value(self, value, connection=None, prepared=False):
+         return value or None
+
+
 if isinstalled('south'):
     from south.modelsinspector import add_introspection_rules
     add_introspection_rules([], ["^orchestra\.models\.fields\.MultiSelectField"])
+    add_introspection_rules([], ["^orchestra\.models\.fields\.NullableCharField"])