With a shadow traffic is duplicated so that it goes to both a main model and also a shadow model. The shadow is typically a newer version being tried out. The responses to requests that reach the end user are only from the main model, not the shadow. But the shadow requests can be logged and the shadow can be monitored. Within Seldon Deploy there are features to:
A wizard to add a shadow:
Visualizing metrics for both default and shadow models:
Promotion of the Shadow to be the main model.
GitOps integration for the whole process, so that all changes can be audited (see GitOps under Architecture)
Request logs include any request to the shadow, with the responses.