Currently, Router directly returns exception response from subcluster to client, which may not have the correct error message, especially when the error message containing a path.
One example, we have a mount path "/a/b" mapped to subclusterA's "/c/d". If user1 does a chown operation on "/a/b", and he doesn't have corresponding privilege, currently the error msg looks like "Permission denied. user=user1 is not the owner of inode=/c/d", which may confuse user. Would be better to reverse the path back to original mount path.