Update hyperv.py

lisa/tools/hyperv.py

@@ -212,16 +212,16 @@ def enable_device_passthrough(self, name: str, mmio_mb: int = 5120) -> None:
     def get_default_switch(
         self, switch_type: HypervSwitchType = HypervSwitchType.EXTERNAL
     ) -> Optional[VMSwitch]:
-        if switch_type in (HypervSwitchType.INTERNAL, HypervSwitchType.EXTERNAL):
-            switch_json = self.node.tools[PowerShell].run_cmdlet(
-                f'Get-VMSwitch | Where-Object {{$_.SwitchType -eq "{switch_type}"}}'
-                "| Select -First 1 | select Name | ConvertTo-Json",
-                force_run=True,
-                fail_on_error=False,
-            )
-        else:
+        if switch_type not in (HypervSwitchType.INTERNAL, HypervSwitchType.EXTERNAL):
             raise LisaException(f"Unknown switch type {switch_type}")
 
+        # get default switch of type `switch_type` from hyperv
+        switch_json = self.node.tools[PowerShell].run_cmdlet(
+            f'Get-VMSwitch | Where-Object {{$_.SwitchType -eq "{switch_type}"}}'
+            "| Select -First 1 | select Name | ConvertTo-Json",
+            force_run=True,
+        )
+
         if not switch_json:
             raise LisaException(f"Could not find default switch of type {switch_type}")
 
@@ -435,8 +435,6 @@ def configure_dhcp(self, dhcp_scope_name: str = "DHCPInternalNAT") -> None:
     def _install(self) -> bool:
         assert isinstance(self.node.os, Windows)
 
-        service: Service = self.node.tools[Service]
-
         # check if Hyper-V is already installed
         if self._check_exists():
             return True
@@ -447,9 +445,11 @@ def _install(self) -> bool:
         # reboot node
         self.node.reboot()
 
+        service: Service = self.node.tools[Service]
         # wait for Hyper-V services to start
-        service.wait_for_service_start("vmms")
+        self.node.tools[Service].wait_for_service_start("vmms")
         service.wait_for_service_start("vmcompute")
+
         return self._check_exists()
 
     def _run_hyperv_cmdlet(