You cannot request this information, because it does not exist.

There is no central registry of nodes, nor do they have identities to begin with. Full nodes do maintain a database of IP addresses of peers they now about, but that is not, and is not intended to be, a comprehensive list of all nodes on the network.

The closest that exists are network crawlers who ask around for IP addresses and try connecting to them (some DNS seed report results based on crawler information), but even that is only an approximation, and can only discover nodes that are reachable. The vast majority of full nodes only make outgoing connections.

getpeerinfo returns information about currently connected peers, but not the entire network. Since Bitcoin is a decentralised peer-to-peer network, no peer can possibly establish an accurate view of the full network connection graph.

Consider how these peer connections are established which are returned by getpeerinfo. When your node is started, it will bootstrap a list of peer endpoint addresses from known seed servers. Once a sufficient number of addresses is acquired, it begins connections (This address list is actively amended as new addresses are propagated to your node after the seed session).

• Outbound connections: Up to N peers on address list acquired during the seed session.
• Inbound connections: Accepts connections from up to M peers connecting to your node
• Manual connections: Configured permanent peers your node (attempts) to maintain connections to.

There is a configurable limit to all types of connections for your node. In any case, the limited view of the network means your node will never have a full view of the global Bitcoin p2p network.