diff --git a/homeassistant/components/fortios/device_tracker.py b/homeassistant/components/fortios/device_tracker.py
index a1507af99dc..e160268e3fc 100644
--- a/homeassistant/components/fortios/device_tracker.py
+++ b/homeassistant/components/fortios/device_tracker.py
@@ -5,6 +5,7 @@ This component is part of the device_tracker platform.
 """
 import logging
 
+from awesomeversion import AwesomeVersion
 from fortiosapi import FortiOSAPI
 import voluptuous as vol
 
@@ -47,49 +48,43 @@ def get_scanner(hass, config):
         return None
 
     status_json = fgt.monitor("system/status", "")
-    fos_major_version = int(status_json["version"][1])
 
-    if fos_major_version < 6 or fos_major_version > 7:
+    current_version = AwesomeVersion(status_json["version"])
+    minimum_version = AwesomeVersion("6.4.3")
+    if current_version < minimum_version:
         _LOGGER.error(
-            "Unsupported FortiOS version, fos_major_version =  %s",
-            fos_major_version,
+            "Unsupported FortiOS version: %s. Version %s and newer are supported",
+            current_version,
+            minimum_version,
         )
         return None
 
-    api_url = "user/device/query"
-    if fos_major_version == 6:
-        api_url = "user/device/select"
-
-    return FortiOSDeviceScanner(fgt, fos_major_version, api_url)
+    return FortiOSDeviceScanner(fgt)
 
 
 class FortiOSDeviceScanner(DeviceScanner):
     """This class queries a FortiOS unit for connected devices."""
 
-    def __init__(self, fgt, fos_major_version, api_url) -> None:
+    def __init__(self, fgt) -> None:
         """Initialize the scanner."""
         self._clients = {}
         self._clients_json = {}
         self._fgt = fgt
-        self._fos_major_version = fos_major_version
-        self._api_url = api_url
 
     def update(self):
         """Update clients from the device."""
-        clients_json = self._fgt.monitor(self._api_url, "")
+        clients_json = self._fgt.monitor("user/device/query", "")
         self._clients_json = clients_json
 
         self._clients = []
 
         if clients_json:
-            if self._fos_major_version == 6:
-                for client in clients_json["results"]:
-                    if client["last_seen"] < 180:
-                        self._clients.append(client["mac"].upper())
-            elif self._fos_major_version == 7:
+            try:
                 for client in clients_json["results"]:
                     if client["is_online"]:
                         self._clients.append(client["mac"].upper())
+            except KeyError as kex:
+                _LOGGER.error("Key not found in clients: %s", kex)
 
     def scan_devices(self):
         """Scan for new devices and return a list with found device IDs."""
@@ -109,15 +104,15 @@ class FortiOSDeviceScanner(DeviceScanner):
         for client in data["results"]:
             if client["mac"] == device:
                 try:
-                    name = ""
-                    if self._fos_major_version == 6:
-                        name = client["host"]["name"]
-                    elif self._fos_major_version == 7:
-                        name = client["hostname"]
+                    name = client["hostname"]
                     _LOGGER.debug("Getting device name=%s", name)
                     return name
                 except KeyError as kex:
-                    _LOGGER.error("Name not found in client data: %s", kex)
-                    return None
+                    _LOGGER.debug(
+                        "No hostname found for %s in client data: %s",
+                        device,
+                        kex,
+                    )
+                    return device.replace(":", "_")
 
         return None