diff --git a/sigi/apps/servicos/jobs/daily/sincroniza_rancher.py b/sigi/apps/servicos/jobs/daily/sincroniza_rancher.py
index 921194f..005cfe2 100644
--- a/sigi/apps/servicos/jobs/daily/sincroniza_rancher.py
+++ b/sigi/apps/servicos/jobs/daily/sincroniza_rancher.py
@@ -117,8 +117,18 @@ class Job(DailyJob):
                 )
 
             try:
-                portal = Servico.objects.get(instancia=iname, tipo_servico=tipo)
+                portal = Servico.objects.get(
+                    instancia=iname, tipo_servico=tipo, data_desativao=None
+                )
                 encontrados += 1
+            except Servico.MultipleObjectsReturned:
+                self._errors.append(
+                    _(
+                        f"Existe mais de um registro ativo da instância {iname}"
+                        f" de {tipo}."
+                    )
+                )
+                continue
             except Servico.DoesNotExist:
                 if iname in self._nomes_gerados:
                     orgao = self._nomes_gerados[iname]
diff --git a/sigi/apps/servicos/migrations/0016_prepare_unique_tipo_servico_instancia_data_desativacao.py b/sigi/apps/servicos/migrations/0016_prepare_unique_tipo_servico_instancia_data_desativacao.py
new file mode 100644
index 0000000..559ac50
--- /dev/null
+++ b/sigi/apps/servicos/migrations/0016_prepare_unique_tipo_servico_instancia_data_desativacao.py
@@ -0,0 +1,33 @@
+# Generated by Django 4.1.2 on 2022-10-24 13:28
+
+from django.db import migrations
+
+
+def instance_names_fw(apps, schema_editor):
+    Servico = apps.get_model("servicos", "Servico")
+    seq = 0
+    for s in Servico.objects.filter(instancia="").exclude(
+        data_desativacao=None
+    ):
+        s.instancia = f"instancia-desativada-{seq}"
+        s.save()
+        seq += 1
+    print(f"{seq} instâncias fakeadas")
+
+
+def instance_names_rw(apps, schema_editor):
+    Servico = apps.get_model("servicos", "Servico")
+    Servico.objects.filter(instancia__startswith="instancia-desativada").update(
+        instancia=""
+    )
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("servicos", "0015_nomeia_instancias"),
+    ]
+
+    operations = [
+        migrations.RunPython(instance_names_fw, instance_names_rw),
+    ]
diff --git a/sigi/apps/servicos/migrations/0017_alter_servico_options_servico_unique_instance.py b/sigi/apps/servicos/migrations/0017_alter_servico_options_servico_unique_instance.py
new file mode 100644
index 0000000..31d211e
--- /dev/null
+++ b/sigi/apps/servicos/migrations/0017_alter_servico_options_servico_unique_instance.py
@@ -0,0 +1,27 @@
+# Generated by Django 4.1.2 on 2022-10-24 13:35
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("servicos", "0016_prepare_unique_tipo_servico_instancia_data_desativacao"),
+    ]
+
+    operations = [
+        migrations.AlterModelOptions(
+            name="servico",
+            options={
+                "verbose_name": "serviço SEIT",
+                "verbose_name_plural": "serviços SEIT",
+            },
+        ),
+        migrations.AddConstraint(
+            model_name="servico",
+            constraint=models.UniqueConstraint(
+                fields=("tipo_servico", "instancia", "data_desativacao"),
+                name="unique_instance",
+            ),
+        ),
+    ]
diff --git a/sigi/apps/servicos/models.py b/sigi/apps/servicos/models.py
index 3158c09..ab53226 100644
--- a/sigi/apps/servicos/models.py
+++ b/sigi/apps/servicos/models.py
@@ -282,6 +282,16 @@ class Servico(models.Model):
 
         return
 
+    class Meta:
+        verbose_name = _("serviço SEIT")
+        verbose_name_plural = _("serviços SEIT")
+        constraints = [
+            models.UniqueConstraint(
+                fields=["tipo_servico", "instancia", "data_desativacao"],
+                name="unique_instance",
+            )
+        ]
+
     def __str__(self):
         return f"{self.tipo_servico.nome} ({self.status_servico})"