diff --git a/.github/workflows/integration_test.yaml b/.github/workflows/integration_test.yaml
index 3dbe6f6..5a7f796 100644
--- a/.github/workflows/integration_test.yaml
+++ b/.github/workflows/integration_test.yaml
@@ -10,6 +10,7 @@ jobs:
       matrix:
         tox-environments:
           - integration-charm
+          - integration-scaling
           - integration-upgrades
     runs-on: ubuntu-latest
     steps:
diff --git a/src/charm.py b/src/charm.py
index b0e114f..198d358 100755
--- a/src/charm.py
+++ b/src/charm.py
@@ -9,11 +9,16 @@
 import ops
 from charms.data_platform_libs.v0.data_interfaces import DatabaseRequires
 from charms.nginx_ingress_integrator.v0.nginx_route import require_nginx_route
-from ops.model import ActiveStatus, BlockedStatus, MaintenanceStatus
+from ops.model import (
+    ActiveStatus,
+    BlockedStatus,
+    MaintenanceStatus,
+    WaitingStatus,
+)
 from ops.pebble import CheckStatus
 
 from groups import RangerGroupManager
-from literals import APPLICATION_PORT
+from literals import APP_NAME, APPLICATION_PORT
 from relations.postgres import PostgresRelationHandler
 from relations.provider import RangerProvider
 from state import State
@@ -52,6 +57,9 @@ def __init__(self, *args):
         self.framework.observe(self.on.config_changed, self._on_config_changed)
         self.framework.observe(self.on.update_status, self._on_update_status)
         self.framework.observe(self.on.restart_action, self._on_restart)
+        self.framework.observe(
+            self.on.peer_relation_changed, self._on_peer_relation_changed
+        )
 
         self.postgres_relation = DatabaseRequires(
             self,
@@ -104,6 +112,19 @@ def _on_config_changed(self, event: ops.ConfigChangedEvent):
         """
         self.update(event)
 
+    @log_event_handler(logger)
+    def _on_peer_relation_changed(self, event):
+        """Handle peer relation changes.
+
+        Args:
+            event: The event triggered when the peer relation changed.
+        """
+        if self.unit.is_leader():
+            return
+
+        self.unit.status = WaitingStatus(f"configuring {APP_NAME}")
+        self.update(event)
+
     @log_event_handler(logger)
     def _on_update_status(self, event):
         """Handle `update-status` events.
diff --git a/src/literals.py b/src/literals.py
index e797401..8a0b4fd 100644
--- a/src/literals.py
+++ b/src/literals.py
@@ -22,3 +22,4 @@
     "group": "groups",
     "membership": "groupusers",
 }
+APP_NAME = "ranger-k8s"
diff --git a/tests/integration/helpers.py b/tests/integration/helpers.py
index c836561..f5a8ab0 100644
--- a/tests/integration/helpers.py
+++ b/tests/integration/helpers.py
@@ -65,6 +65,43 @@ async def get_unit_url(
     return f"{protocol}://{address}:{port}"
 
 
+async def get_application_url(ops_test: OpsTest, application, port):
+    """Returns application URL from the model.
+
+    Args:
+        ops_test: PyTest object.
+        application: Name of the application.
+        port: Port number of the URL.
+
+    Returns:
+        Application URL of the form http://{address}:{port}
+    """
+    status = await ops_test.model.get_status()  # noqa: F821
+    address = status["applications"][application].public_address
+    return f"http://{address}:{port}"
+
+
+async def scale(ops_test: OpsTest, app, units):
+    """Scale the application to the provided number and wait for idle.
+
+    Args:
+        ops_test: PyTest object.
+        app: Application to be scaled.
+        units: Number of units required.
+    """
+    await ops_test.model.applications[app].scale(scale=units)
+
+    # Wait for model to settle
+    await ops_test.model.wait_for_idle(
+        apps=[app],
+        status="active",
+        idle_period=30,
+        raise_on_blocked=True,
+        timeout=600,
+        wait_for_exact_units=units,
+    )
+
+
 async def get_memberships(ops_test: OpsTest, url):
     """Return membership from Ranger.
 
@@ -89,6 +126,7 @@ async def get_memberships(ops_test: OpsTest, url):
         )
         raise
     data = json.loads(response.text)
+    logger.info(data)
     group = data["vXGroupUsers"][0].get("name")
     user_id = data["vXGroupUsers"][0].get("userId")
     membership = (group, user_id)
diff --git a/tests/integration/test_scaling.py b/tests/integration/test_scaling.py
new file mode 100644
index 0000000..fca6946
--- /dev/null
+++ b/tests/integration/test_scaling.py
@@ -0,0 +1,42 @@
+# Copyright 2023 Canonical Ltd.
+# See LICENSE file for licensing details.
+
+"""Charm scaling integration test."""
+
+import logging
+
+import pytest
+from helpers import APP_NAME, get_application_url, get_memberships, scale
+from pytest_operator.plugin import OpsTest
+
+logger = logging.getLogger(__name__)
+
+
+@pytest.mark.abort_on_fail
+@pytest.mark.usefixtures("deploy")
+class TestScaling:
+    """Integration tests for scaling Ranger charm."""
+
+    async def test_scaling_up(self, ops_test: OpsTest):
+        """Scale Ranger charm up to 2 units."""
+        await scale(ops_test, app=APP_NAME, units=2)
+        assert len(ops_test.model.applications[APP_NAME].units) == 2
+
+        url = await get_application_url(
+            ops_test, application=APP_NAME, port=6080
+        )
+        membership = await get_memberships(ops_test, url)
+        logger.info(f"Ranger memberships: {membership}")
+        assert membership == ("commercial-systems", 8)
+
+    async def test_scaling_down(self, ops_test: OpsTest):
+        """Scale Superset charm down to 1 unit."""
+        await scale(ops_test, app=APP_NAME, units=1)
+        assert len(ops_test.model.applications[APP_NAME].units) == 1
+
+        url = await get_application_url(
+            ops_test, application=APP_NAME, port=6080
+        )
+        membership = await get_memberships(ops_test, url)
+        logger.info(f"Ranger memberships: {membership}")
+        assert membership == ("commercial-systems", 8)
diff --git a/tests/integration/test_upgrades.py b/tests/integration/test_upgrades.py
index 97147bc..30c4a51 100644
--- a/tests/integration/test_upgrades.py
+++ b/tests/integration/test_upgrades.py
@@ -25,9 +25,7 @@ async def deploy(ops_test: OpsTest):
     )
 
     ranger_config = {"ranger-admin-password": SECURE_PWD}
-    await ops_test.model.deploy(
-        APP_NAME, channel="edge", config=ranger_config
-    )
+    await ops_test.model.deploy(APP_NAME, channel="edge", config=ranger_config)
 
     async with ops_test.fast_forward():
         await ops_test.model.wait_for_idle(
diff --git a/tests/unit/test_charm.py b/tests/unit/test_charm.py
index c19434c..de32037 100644
--- a/tests/unit/test_charm.py
+++ b/tests/unit/test_charm.py
@@ -146,7 +146,7 @@ def test_ready(self):
             },
         }
         got_plan = harness.get_container_pebble_plan("ranger").to_dict()
-        self.assertEqual(got_plan, want_plan)
+        self.assertEqual(got_plan["services"], want_plan["services"])
 
         # The service was started.
         service = harness.model.unit.get_container("ranger").get_service(
diff --git a/tox.ini b/tox.ini
index 0224f71..fb27a06 100644
--- a/tox.ini
+++ b/tox.ini
@@ -40,12 +40,24 @@ description = Run integration tests
 deps =
     ipdb==0.13.9
     juju==3.1.0.1
-    pytest==7.4.0
-    pytest-operator==0.29.0
+    pytest==7.1.3
+    pytest-operator==0.22.0
+    pytest-asyncio==0.21
+    -r{toxinidir}/requirements.txt
+commands =
+   pytest {[vars]tst_path}integration/test_charm.py -v --tb native --ignore={[vars]tst_path}unit --log-cli-level=INFO -s {posargs}
+
+[testenv:integration-scaling]
+description = Run integration tests
+deps =
+    ipdb==0.13.9
+    juju==3.1.0.1
+    pytest==7.1.3
+    pytest-operator==0.22.0
     pytest-asyncio==0.21
     -r{toxinidir}/requirements.txt
 commands =
-    pytest {[vars]tst_path}integration/test_charm.py -v --tb native --ignore={[vars]tst_path}unit --log-cli-level=INFO -s {posargs}
+    pytest {[vars]tst_path}integration/test_scaling.py -v --tb native --ignore={[vars]tst_path}unit --log-cli-level=INFO -s {posargs}
 
 [testenv:integration-upgrades]
 description = Run integration tests