Add multiple notaries in CORDA - corda

Question

I am trying to create a DLT with 4 nodes and 2 notaries where each notary is responsible for communicating with 2 nodes.
Sample Gradle config
task deployNodes(type: net.corda.plugins.Cordform, dependsOn: ['jar']) {
directory "./build/nodes"
networkMap "O=Controller,L=London,C=GB"
node {
name "O=Controller,L=London,C=GB"
advertisedServices = ["corda.notary.validating"]
p2pPort 10002
rpcPort 10003
cordapps = ["net.corda:corda-finance:$corda_release_version"]
}
node {
name "O=ControllerNY,L=New York,C=US"
advertisedServices = ["corda.notary.validating"]
p2pPort 10004
rpcPort 10005
cordapps = ["net.corda:corda-finance:$corda_release_version"]
}
node {
name "O=PartyA,L=London,C=GB"
advertisedServices = []
p2pPort 10006
rpcPort 10007
webPort 10008
cordapps = ["net.corda:corda-finance:$corda_release_version"]
rpcUsers = [[ user: "user1", "password": "test", "permissions": []]]
}
node {
name "O=PartyB,L=London,C=GB"
advertisedServices = []
p2pPort 10009
rpcPort 10010
webPort 10011
cordapps = ["net.corda:corda-finance:$corda_release_version"]
rpcUsers = [[ user: "user1", "password": "test", "permissions": []]]
}
node {
name "O=PartyC,L=New York,C=US"
advertisedServices = []
p2pPort 10012
rpcPort 10013
webPort 10014
cordapps = ["net.corda:corda-finance:$corda_release_version"]
rpcUsers = [[ user: "user1", "password": "test", "permissions": []]]
}
node {
name "O=PartyD,L=New York,C=US"
advertisedServices = []
p2pPort 10015
rpcPort 10016
webPort 10017
cordapps = ["net.corda:corda-finance:$corda_release_version"]
rpcUsers = [[ user: "user1", "password": "test", "permissions": []]]
}
}
how can i add both controller, controllerNY to network so that it picks it as notary and not as a normal node

Answer 1

Both Controller and ControllerNY will be added to your network as notaries in this case, because they both advertise a notary service.
Each node is then free to use either notary for a given transaction. You pick your notary within the flow using something like:
serviceHub.networkMapCache.getNotary(notaryToUse)
Or
serviceHub.networkMapCache.notaryIdentities.single { it.name.organisation == notaryToUse }