Consul Service Mesh with Other Services

If I want to use service mesh with consul, is it all or nothing? I have some services with k8s, but then I also have services running in non-k8 workloads. If I just want the mesh for the k8s workloads, is that possible? Or if I enable connect will it negatively affect all the services?

Yes, it is possible to only use service mesh for a subset of the workloads in your cluster. Any service not configured with a sidecar proxy will be considered by Consul to be outside the mesh.