# Private Network¶

To build a private chain, it is necessary to deploy at least one fullnode running by SR to produces blocks, and any number of fullnodes to synchronize blocks and broadcast transactions. Only one SR node and one fullnode are set up in this example. Before the deployment, please install the Oracle JDK 1.8 first, and then you need to prepare at least two TRON network address and save the address and private key. You can use wallet-cli or Tronlink to create address.

# Deployment Guide¶

The process of building a node on private chain is the same as that on mainnet. The difference is the content of the node configuration file. The most important step to build a private chain is to modify the configuration items in the configuration file, so that the nodes can form a private network for node discovery, block synchronization and broadcast transactions.

1. Create deployment directory

Create deployment directory, it is recommended to put the two fullnodes in different directories.

$mkdir SR$ mkdir FullNode


2. Obtain FullNode.jar

Obtain FullNode.jar, then put it into the SR and FullNode directories respectively.

$cp FullNode.jar ./SR$ cp FullNode.jar ./FullNode


3. Obtain the node's config file private_net_config.conf

Obtain the node's config file private_net_config.conf, then put it into the SR and FullNode directories respectively, and modify the file names respectively to supernode.conf, fullnode.conf.

$cp private_net_config.conf ./SR/supernode.conf$ cp private_net_config.conf ./FullNode/fullnode.conf


4. Modify the configuration file of each node

Please modify each configuration item of the node in turn according to the instructions in the following table:

Config Item SR Fullnode FullNode Description
localwitness The private key of witness address Please do not fill in data Generating blocks requires signing with a private key
genesis.block.witnesses Witness address The same as SR node's Genesis block related configuration
genesis.block.Assets Preset TRX for specific accounts. Add the pre-prepared address to the end and specify its TRX balance as needed The same as SR node's Genesis block related configuration
p2p.version any positive integer except for 11111 the same as SR node's Only nodes of the same p2p version can shake hands successfully
seed.node Please do not fill in data Change the seed.node ip.list in the configuration file to the IP address and the port (listen.port) of the SR Enables fullnode to establish connection with SR node and synchronize data
needSyncCheck false true Set the first SR’s needSyncCheck to false, other SRs true
node.discovery.enable true true If it is false, the current node will not be discovered by other nodes
block.proposalExpireTime 600000 The same as SR node's The default proposal effective time is 3 days: 259200000 (ms), if you want to quickly pass the proposal, you can set this item to a smaller value, such as 10 minutes, that is, 600000ms
block.maintenanceTimeInterval 300000 The same as SR node's The defaul maintenance time interval is 6 hours: 21600000 (ms), if you want to pass the proposal quickly, you can set this item to a smaller value, such as five minutes, that is, 300000ms.
committee.allowSameTokenName 1 1 Allow same token name
committee.allowTvmTransferTrc10 1 1 Allow tvm transfer TRC10
5. Modify the port in the configuration file, and configure the SR and FullNode with different port numbers. Note, this step is only required if SR and FullNode are running on the same machine, otherwise, this step can be skipped.

• listen.port ： p2p listen port
• http port： Http listen port
• rpc port： rpc listen port
6. Startup the node

The fullnode that produces blocks has the different startup command with the fullnodes that do not produce blocks:

• Fullnode that produces blocks
$java -Xmx6g -XX:+HeapDumpOnOutOfMemoryError -jar FullNode.jar --witness -c supernode.conf  • Fullnode $ java -Xmx6g -XX:+HeapDumpOnOutOfMemoryError -jar FullNode.jar  -c fullnode.conf

7. Modify the dynamic parameters of the private chain

In order to be the same as the main network environment, the dynamic parameters of the private chain need to be modified to be consistent with those of the main network. The modification of dynamic parameters can be done through proposals. The SR account can use wallet-cli or fullnode http API wallet/proposalcreateto create proposals, wallet/proposalapprove to approve proposals.

The following are the dynamic parameters and values sorted out according to the proposals passed by the mainnet successively. SR can directly use the following commands to create a proposal to complete the modification of all the dynamic parameters of the private chain at one time.

var TronWeb = require('tronweb');
var tronWeb = new TronWeb({
fullHost: 'http://localhost:16887',
privateKey: 'c741f5c0224020d7ccaf4617a33cc099ac13240f150cf35f496db5bfc7d220dc'
})

var unsignedProposal1Txn = await tronWeb.transactionBuilder.createProposal([{"key":9,"value":1},{"key":10,"value":1},{"key":11,"value":280},{"key":19,"value":90000000000},{"key":15,"value":1},{"key":18,"value":1},{"key":16,"value":1},{"key":20,"value":1},{"key":26,"value":1},{"key":30,"value":1},{"key":5,"value":16000000},{"key":31,"value":160000000},{"key":32,"value":1},{"key":39,"value":1},{"key":41,"value":1},{"key":3,"value":1000},{"key":47,"value":10000000000},{"key":49,"value":1},{"key":13,"value":80},{"key":7,"value":1000000},{"key":61,"value":1500},{"key":63,"value":1}],"41D0B69631440F0A494BB51F7EEE68FF5C593C00F0")
var signedProposal1Txn = await tronWeb.trx.sign(unsignedProposal1Txn, "c741f5c0224020d7ccaf4617a33cc099ac13240f150cf35f496db5bfc7d220dc");
var receipt1 = await tronWeb.trx.sendRawTransaction(signedProposal1Txn);

setTimeout(async function() {
console.log("Vote proposal!")
var unsignedVoteP1Txn = await tronWeb.transactionBuilder.voteProposal(1, true, tronWeb.defaultAddress.hex)
var signedVoteP1Txn = await tronWeb.trx.sign(unsignedVoteP1Txn, "c741f5c0224020d7ccaf4617a33cc099ac13240f150cf35f496db5bfc7d220dc");
var rtn1 = await tronWeb.trx.sendRawTransaction(signedVoteP1Txn);
}, 1000)