Can someone shed some light on this interesting, but confusing piece of documentation:
Specifically, there are a few interesting points:
1. Combined with a read of the config utility manual, there is a difference between a "host" and a "node". Can someone elaborate?
2. If I wanted two gateways per node, I'd have to define a 2nd "host", right? How are the HGID's/HN's/host names associated with eachother?
3. and this is what I'm leading up to, and that the documentation doesn't explain clearly... If one has a node with multiple IP addresses, how do you control which IP address the gateway vproc binds to?
ie, should there literally be hosts file entries like
like the document indicates? If so, how does it know that "hgid1" is the name of the HGID/HN?
A host group / logical host ID is just an identifier for a collection of resources, which potentially are on different nodes (servers).
The host group is specified when LAN adapters are added to the database configuration via PUT (Parallel Upgrade Tool). If you wanted two GTW (gateway) VProcs on the same node, you'd need the OS to present two different adapters to PUT. And multiple adapters on the node can be assigned to the same host group. The GTW isn't bound directly to an IP address.
The host group is also specified when PE or GTW VProcs are added to the configuration.
The hostnames are not part of the database configuration; they are for client connections.