Lesson 5: Agent, Network, & Node¶
Now, you're ready to connect your server with your agent.
Agent¶
To do that, please login to your server and go to the agent management page.
Click on the "New" button to register a new agent with a URL linked to your agent host. The default agent port is 5001.
Info
Even if you register the agent successfully, it doesn't mean that the server can access the agent successfully. The server will only try to connect the agent when it has to operate nodes, and this will happen later in this lesson when we create a network.
Nodes¶
Image¶
Compared to the usual pratice of Hyperledger Fabric, Hyperledger Cello doesn't use the official peer and orderer images to deploy nodes. Instead, Hyperledger Cello uses its own customized Hyperledger Fabric node images, which combines all Hyperledger Fabric binaries into one single image.
To build that, run
make fabric
The image will be tagged as hyperledger/fabric:2.5.10.
The "Quickstart" way
The quickstart make local command we mentioned in lesson 2 and lesson 3 will also build the node image for you.
Create peers and orderers¶
Info
If you don't know what peers and orderers are, please check out Peers.
Go to the node management page and click on the "New" button. You can choose to create either a peer or an orderer and name it.
To create a channel in the following lessons, you must create at least 1 peer and 1 orderer.
You should name them like hostnames just as you do for your organization because their names will also be used as a part of their hostnames.
Network¶
You may notice that currently the status of your nodes are "created", and you don't see any container like Hyperledger Fabric nodes running on your agent host. That's because the server won't ask agents to deploy nodes until they're in a network.
Thus, you have to create a network to place your nodes.
Info
Network actually derives from a deprecated idea system channel in Hyperledger Fabric, which means it also will be deprecated in the near future. However, we still need it here to run our nodes currently.
Go to the network management page and click on the "New" button to create a network.
After you create a network successfully, even though it doesn't seem like there is anything happening, you can go to the node management page to see if your node status turns to green with a "running" label. Please wait about 5 minutes if you don't see any change. After that, there may be something wrong in your deployment. You can check the container logs by executing the docker logs command with the api engine or agent container or consider contacting us.
Otherwise, you should see your nodes running as containers on your agent host by executing
docker ps
Info
A peer container will be named as the peer name concatenated with the organization name.
An orderer container will be named as the organization name with its first part replaced with the orderer name.
For example, if there is an organization named "org1.cello.com" with a peer named "peer1" and an orderer named "orderer1", their containers should be named as "peer1.org1.cello.com" and "orderer1.cello.com".
Such a naming method emphasizes that an orderer doesn't solely belong to its organization in a Hyperledger Fabric network.
Conclusion¶
That's it! You have successfully connected your Hyperledger Cello server with your agent🎉!
Moreover, you also managed to deploy some Hyperledger Fabric running nodes!
In the next lesson, we'll talk about how you can create a channel with them.
See you then👋!
Note
Network is not Blockchain, and there is no block on it. Network is just an abstract idea about what connects between organization nodes.