S5/S8 splitting based on service/APN

[crbertoldo]

We have a use case (roaming) in which we need to do local breakout for non-IMS traffic (S5 interface) with Magma, and remote forwarding (S8 interface) for IMS one. I.e., Magma powers the managed/visited network, and the remote EPC powers the home one. On the UE, we would have two APNs: one for IMS, and another for non-IMS. Question: is this setup known/tested? If so, with which version? If not, what challenges could we see? We know the S5/S8 splitting by home and visitor subscribers, but not by both home/visitor subscribers and APN. Anyway, for this use case, we can use only the remote HSS, so the local_subscriber (see the following screenshot) table will be always empty.

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