waagent: specify the waagent command when previous command has errors

lisa/sut_orchestrator/azure/tools.py

@@ -63,12 +63,19 @@ def _initialize(self, *args: Any, **kwargs: Any) -> None:
 
     def get_version(self) -> str:
         result = self.run("-version")
-        if isinstance(self.node.os, CBLMariner):
-            self._command = "/usr/bin/waagent"
-        else:
-            self._command = "/usr/sbin/waagent"
+
         if result.exit_code != 0:
+            if self.node.tools[Ls].path_exists("/usr/bin/waagent"):
+                self._command = "/usr/bin/waagent"
+            elif self.node.tools[Ls].path_exists("/usr/sbin/waagent"):
+                self._command = "/usr/sbin/waagent"
+            else:
+                raise LisaException(
+                    "waagent is not found in system path variable,"
+                    " /usr/bin and /usr/sbin."
+                )
             result = self.run("-version")
+
         # When the default command python points to python2,
         # we need specify python3 clearly.
         # e.g. bt-americas-inc diamondip-sapphire-v5 v5-9 9.0.53.