According to the docs,
cardano-cli and other Cardano software components need to know where the node socket file is located. We saved it to the path $HOME/cardano/db/node.socket in the previous example. The components read the shell environment variable CARDANO_NODE_SOCKET_PATH to find this.
It seems like this node socket file is specific to either the testnet or the mainnet, not both. Are you supposed to change the CARDANO_NODE_SOCKET_PATH
environment variable every time you want to use the CLI tools with a different network?