View Channel Blockchain and Download Blocks

Q

How to View Blockchain and Download Blocks of a Hyperledger Fabric Channel?

✍: FYIcenter.com

A

You can follow this tutorial to View Blockchain and Download Blocks of a Hyperledger Fabric Channel.

1. Connect to the CLI container of the Hyperledger Fabric network:

$ docker exec -it cli bash
bash-4.4#

2. List channels joined by the default peer:

bash-4.4# echo $CORE_PEER_ADDRESS
peer0.org1.example.com:7051

bash-4.4# peer channel list

Channels peers has joined:
mychannel

3. Get the blockchain info of a given channel:

bash-4.4# peer channel getinfo -c mychannel

Blockchain info: 
{"height":6,
 "currentBlockHash":"rriN9xJHYX+c2xo7qIqNvxNlcGFRAADgA4hIg7byvwE=",
 "previousBlockHash":"KDjkXFvRJAcYTp2ralLNhMAD3eZc0LxfQyHr9DZgl0M="
}

4. Download (fetch) the newest block:

bash-4.4# peer channel fetch newest newest.block -c mychannel
[channelCmd] InitCmdFactory -> INFO 001 Endorser and orderer connections initialized
[cli.common] readBlock -> INFO 002 Received block: 5

bash-4.4# ls -l
-rw-r--r--    1 root     root          4921 Apr  1 18:00 newest.block

5. Download (fetch) the first block:

bash-4.4# peer channel fetch 0 newest.block -c mychannel
[channelCmd] InitCmdFactory -> INFO 001 Endorser and orderer connections initialized
[cli.common] readBlock -> INFO 002 Received block: 0

bash-4.4# ls -l
-rw-r--r--    1 root     root         15995 Apr 13 18:07 first.block
-rw-r--r--    1 root     root          4921 Apr  1 18:00 newest.block

Note that block 5 is the 6th block of the blockchain, because the first block is labeled as block 0.

 

⇒ Inspect Transaction Blocks of Channel Blockchain

⇐ "peer chaincode invoke" on BYFN

⇑ BYFN (Build Your First Network)

⇑⇑ Hyperledger Tutorials

2020-08-13, 798👍, 0💬