[mpich-discuss] Selecting a specific libfabric fabric/domain

[eric at bit32.net]

Hi there,

I'm using MPICH with ch4:ofi, and I'm wondering how to select which 
fabric/domain MPICH will open. I can select the provider with 
MPIR_CVAR_OFI_USE_PROVIDER, but suppose that the provider has two 
disjoint fabrics with equivalent capabilities. E.g., suppose I have two 
ethernet NICs connected to private networks:

provider: sockets
     fabric: 192.168.1.0/24
     domain: eth0
     version: 2.0
     type: FI_EP_RDM
     protocol: FI_PROTO_SOCK_TCP
provider: sockets
     fabric: 10.0.1.0/24
     domain: eth1
     version: 2.0
     type: FI_EP_RDM
     protocol: FI_PROTO_SOCK_TCP


Is there a tunable to pick which will be used?

Thanks,
Eric