We already have an exception for cases where some component is not configured at all (UnconfiguredSubsystem). For example, when the user tries run restart ipsec but IPsec is not configured at all, it's perfectly logical.

However, there are cases when commands for single objects like run reset vpn ipsec site-to-site peer may be called on non-existing peers/interfaces/etc. Returning UnconfiguredSubsystem feels too overreaching — the subsystem is there, just doesn't have a particular object.

DataUnavailable is more suited for temporary errors.

I believe we need a distinct exception, e.g., UnconfiguredObject.