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The purpose of ZeroConfig or mDNS is to discover the IP services locally on the network. It extends the DNS protocol to support mDNS features. Unlike normal DNS query is to ask which IP address is for the domain name for 'ubuntu-4321-http-sever.local', the mDNS query is to multicast the question on the LAN for services. For our local data-store application usage of mDNS, hopefully the 'ubuntu-4321-http-server' host will reply to the service query and supply the IP address information also. There are many services defined in the IANA, https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.txt, and in this feature we will use 'workstation', 'http' and 'https'. At least one of them needs to be configured to advertise in the local data-store VM side. There is no default service enabled even the 'Avahi' is running. The EVE-OS side does not really care about which services will reply, it has the local domain name, and it needs to have a mapping to the IP address it can use for downloading remote endpoint, and any service reply for the mDNS query will have the host-name and IP address.
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