• Introduce
• Generate your own key
• Generate a second set of keys
• Modify the existing chain specification
• Convert the chain specification to use the original format
• Start the first node
• Allow other participants to join
• Substrate Tutorials , Substrate course
• Contact Contact information

• Introduce

This tutorial explains how to use a set of private validators to start a small independent blockchain network .

All blockchains require the nodes in the network to agree on the message set and its order , To successfully create blocks and advance from one block to the next . Each block represents the data state at a specific point in time , The agreement of the node on this state is called consensus . There are several different algorithms for reaching consensus , Include ：

• The workload proof consensus depends on the computational work done by the verifier node to add valid blocks to the chain .

• The equity certification consensus selects the verifier to add effective blocks to the chain according to the cryptocurrency holdings they lock into the equity in the network .

• Authoritative consensus evidence relies on a set of approved account identities to act as verifiers . The node associated with the approved account has the right to put the transaction into the block .

Substrate The node template uses the authoritative proof consensus model , Also known as authority wheel or Aura Consensus .Aura The consensus agreement limits the block production to the authorized account that creates the block in a circular way （ jurisdiction ） In the rotation list of .

In this tutorial , You will see how this consensus model works in practice , First , By using predefined accounts as part of the node template , Then add new permissions to the approval set .

• Generate your own key

Now you know how to use command line options to start and connect a running node as a peer , You can generate your own key , Instead of using a predefined account key . It's important to remember , Each participant in the blockchain network is responsible for generating a unique key .

You have used some command-line options to use predefined alice and bob The account starts the local blockchain node . You can also use the command line option to generate a random key to communicate with Substrate Use it together .

As best practice , When you generate a key for the production blockchain , You should use an air gap computer that is never connected to the Internet . At least , Before generating any keys that you intend to use on public or private blockchains that are not under your control , You should disconnect from the Internet .

however , For this tutorial , You can use node templatekey The subcommand generates a random key locally and keeps the same with Internet The connection of .

• Open the terminal housing on your computer .

• Switch to compile Substrate The root directory of the node template .

• Generate random key phrases and keys by running the following command ：

./target/release/node-template key generate --scheme Sr25519 --password-interactive

• Type the password for the generated key .

This command generates the key and displays output similar to the following ：

Secret phrase:  pig giraffe ceiling enter weird liar orange decline behind total despair fly
Secret seed:       0x0087016ebbdcf03d1b7b2ad9a958e14a43f2351cd42f2f0a973771b90fb0112f
Public key (hex):  0x1a4cc824f6585859851f818e71ac63cf6fdc81018189809814677b2a4699cf45
Account ID:        0x1a4cc824f6585859851f818e71ac63cf6fdc81018189809814677b2a4699cf45
Public key (SS58): 5CfBuoHDvZ4fd8jkLQicNL8tgjnK8pVG9AiuJrsNrRAx6CNW
SS58 Address:      5CfBuoHDvZ4fd8jkLQicNL8tgjnK8pVG9AiuJrsNrRAx6CNW

• Use the passphrase of the account you just generated Ed25519 Signature scheme derived key .

for example , Run a command similar to the following ：

./target/release/node-template key inspect --password-interactive --scheme Ed25519 "pig giraffe ceiling enter weird liar orange decline behind total despair fly"

• Type the password used to generate the key .

This command displays output similar to the following ：

Secret phrase `pig giraffe ceiling enter weird liar orange decline behind total despair fly` is account:
Secret seed:       0x0087016ebbdcf03d1b7b2ad9a958e14a43f2351cd42f2f0a973771b90fb0112f
Public key (hex):  0x2577ba03f47cdbea161851d737e41200e471cd7a31a5c88242a527837efc1e7b
Public key (SS58): 5CuqCGfwqhjGzSqz5mnq36tMe651mU9Ji8xQ4JRuUTvPcjVN
Account ID:        0x2577ba03f47cdbea161851d737e41200e471cd7a31a5c88242a527837efc1e7b
SS58 Address:      5CuqCGfwqhjGzSqz5mnq36tMe651mU9Ji8xQ4JRuUTvPcjVN

• Generate a second set of keys

• For this tutorial , The private network contains only two nodes , So you need two sets of keys . You have several options to continue this tutorial ：

You can use the key for one of the predefined accounts .

You can repeat the steps in the previous section using a different identity on the local computer , To generate a second key pair .

You can derive a child key pair to simulate a second identity on the local computer .

You can recruit other participants to generate the keys needed to join your private network .

• For illustrative purposes , The second set of keys used in this tutorial is ：

Sr25519：5EJPj83tJuJtTVE2v7B9ehfM7jNT44CBFaPWicvBwYyUKBS6 be used for aura.
Ed25519：5FeJQsfmbbJLTH1pvehBxrZrT5kHvJFj84ZaY5LK7NU87gZS by grandpa.

• Modify the existing chain specification

After generating the key for the blockchain , You can use these key pairs to create custom chain specifications , Then share your custom chain specification with trusted network participants called validators .

To enable others to participate in your blockchain network , You should make sure they generate their own keys . If other participants have already generated their key pairs , You can create custom chain specifications to replace local The chain specification you used before .

This tutorial explains how to create a two node network . You can follow the same steps to add more nodes to your network .

before , You use the command line options to use the predefined local Chain specification adds nodes to blockchain .–chain local No need to write a new chain specification , You can modify the specifications used before .

To create a new chain specification based on an existing specification ：

• Open the terminal housing on your computer .

• Switch to compile Substrate The root directory of the node template .

• Export the local chain specification to customSpec.json Name the file by running the following command ：

./target/release/node-template build-spec --disable-default-bootnode --chain local > customSpec.json

• customSpec.json Preview the first few fields in the file by running the following command ：

head customSpec.json

This command displays the first field in the file . for example ：

{
  "name": "Local Testnet",
  "id": "local_testnet",
  "chainType": "Local",
  "bootNodes": [],
  "telemetryEndpoints": null,
  "protocolId": null,
  "properties": null,
  "consensusEngine": null,
  "codeSubstitutes": {},

• customSpec.json Preview the last field in the file by running the following command ：

tail -n 80 customSpec.json

This command shows Wasm The last part after the binary field , Include details of several pallets used in the runtime , for example sudo and balances Tray .

• customSpec.json Open the file in a text editor .

• modify aura Field to add... For each network participant Sr25519 SS58 Address key to specify the node that is authorized to create the block .

"aura": {
    "authorities": [
      "5CfBuoHDvZ4fd8jkLQicNL8tgjnK8pVG9AiuJrsNrRAx6CNW",
      "5EJPj83tJuJtTVE2v7B9ehfM7jNT44CBFaPWicvBwYyUKBS6"
    ]
  },

• Modify this grandpa Field to add... For each network participant Ed25519 SS58 Address key to specify the node authorized to complete the block .

"grandpa": {
    "authorities": [
      [
        "5CuqCGfwqhjGzSqz5mnq36tMe651mU9Ji8xQ4JRuUTvPcjVN",
        1
      ],
      [
        "5FeJQsfmbbJLTH1pvehBxrZrT5kHvJFj84ZaY5LK7NU87gZS",
        1
      ]
    ]
  },

• Convert the chain specification to use the original format

After you have prepared the chain specification containing the information you want to use , You must first convert it to the original specification , Then you can use it . The original chain specification contains the same information as the untransformed specification . however , The original chain specification also contains encoded storage keys that nodes use to reference data in their local storage . Distributing the original chain specification ensures that each node stores data with the correct storage key .

To convert the chain specification to use the original format ：

Open the terminal housing on your computer .

Switch to compile Substrate The root directory of the node template .

By running the following command customSpec.json The chain specification is converted to the original format with the file name ：customSpecRaw.json

./target/release/node-template build-spec --chain=customSpec.json --raw --disable-default-bootnode > customSpecRaw.json

• Start the first node

As the first participant in the private blockchain network , You are responsible for starting the first node , be called bootnode.

Start the first node ：

• Open the terminal housing on your computer .

• Switch to compile Substrate The root directory of the node template .

• By running a command similar to the following , Start the first node using the custom chain specification ：

./target/release/node-template \
--base-path /tmp/node01 \
--chain ./customSpecRaw.json \
--port 30333 \
--ws-port 9945 \
--rpc-port 9933 \
--telemetry-url "wss://telemetry.polkadot.io/submit/ 0" \
--validator \
--rpc-methods Unsafe \
--name MyNode01

• Add the key to the keystore
After starting the first node , No blocks have been generated . The next step is to add two types of keys to the keystore of each node in the network .

For each node ：

add to aura Permission key to enable block production .

add to grandpa Permission key to enable block completion .

To insert a key into the keystore ：

• Open the terminal housing on your computer .

• Switch to compile Substrate The root directory of the node template .

• Insert... By running a command similar to the following aura Keys generated from subcommands ：key

./target/release/node-template key insert --base-path /tmp/node01 \
--chain customSpecRaw.json \
--scheme Sr25519 \
--suri <your-secret-seed> \
--password-interactive \
--key-type aura

• Insert... By running a command similar to the following grandpa Keys generated from subcommands ：key

./target/release/node-template key insert --base-path /tmp/node01 \
--chain customSpecRaw.json \
--scheme Ed25519 \
--suri <your-secret-key> \
--password-interactive \
--key-type gran

• node01 Verify that your key is in the keystore by running the following command ：

ls /tmp/node01/chains/local_testnet/keystore

This command displays output similar to the following ：

617572611441ddcb22724420b87ee295c6d47c5adff0ce598c87d3c749b776ba9a647f04
6772616e1441ddcb22724420b87ee295c6d47c5adff0ce598c87d3c749b776ba9a647f04

• Allow other participants to join

You can now use –bootnodes and –validator Command line options allow other authenticators to join the network .

Add a second authenticator to the private network ：

• Open the terminal housing on the second computer .

• Switch to compile Substrate The root directory of the node template .

• Start the second blockchain node by running the following command ：

./target/release/node-template \
--base-path /tmp/node02 \
--chain ./customSpecRaw.json \
--port 30334 \
--ws-port 9946 \
--rpc-port 9934 \
--telemetry-url "wss://telemetry.polkadot.io/submit/ 0" \
--validator \
--rpc-methods Unsafe \
--name MyNode02 \
--bootnodes /ip4/127.0.0.1/tcp/30333/p2p/12D3KooWLmrYDLoNTyTYtRdDyZLWDe1paxzxTw5RgjmHLfzW96SX \
--password-interactive

• Add... By running a command similar to the following aura Keys generated from subcommands ：key

./target/release/node-template key insert --base-path /tmp/node02 \
--chain customSpecRaw.json \
--scheme Sr25519 \
--suri <second-participant-secret-seed> \
--password-interactive \
--key-type aura

• By running a command similar to the following ,grandpa Add the key generated from the subcommand to the local keystore ：key

./target/release/node-template key insert --base-path /tmp/node02 \
--chain customSpecRaw.json \
--scheme Ed25519 \
--suri <second-participant-secret-seed> \
--password-interactive \
--key-type gran

• node02 Verify that your key is in the keystore by running the following command ：

ls /tmp/node02/chains/local_testnet/keystore

This command displays output similar to the following ：

617572611a4cc824f6585859851f818e71ac63cf6fdc81018189809814677b2a4699cf45
6772616e1a4cc824f6585859851f818e71ac63cf6fdc81018189809814677b2a4699cf45

Substrate The node is inserting grandpa The key needs to be restarted , So you must shut down and restart the node before you see the block complete .

• Press Control-c Close the node .

• Restart the second blockchain node by running the following command ：

./target/release/node-template \
--base-path /tmp/node02 \
--chain ./customSpecRaw.json \
--port 30334 \
--ws-port 9946 \
--rpc-port 9934 \
--telemetry-url "wss://telemetry.polkadot.io/submit/ 0" \
--validator \
--rpc-methods Unsafe \
--name MyNode02 \
--bootnodes /ip4/127.0.0.1/tcp/30333/p2p/12D3KooWLmrYDLoNTyTYtRdDyZLWDe1paxzxTw5RgjmHLfzW96SX \
--password-interactive

Add their keys to their respective keystores at both nodes （ be located and Next ）/tmp/node01 and /tmp/node02 After reboot , You should see the same Genesis block and state root hash .

You should also see that each node has a peer node （1 peers）, And they generate a block proposal （best: #2 (0xe111…c084)）. After a few seconds , You should see that the new block on both nodes is complete .

• Substrate Tutorials , Substrate course

CN chinese Github Substrate course : github.com/565ee/Substrate_CN
CN chinese CSDN Substrate course : blog.csdn.net/wx468116118
EN english Github Substrate Tutorials : github.com/565ee/Substrate_EN
EN english dev.to Substrate Tutorials : dev.to/565ee

• Contact Contact information

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