What is the need of docker in hyperledger fabric? Also why we need to run every process in different docker containers? Because It's putting extra overhead on the system.
Is there any alternative to docker in such scenario?
Up to this date, Docker daemon is required for Fabric to run chaincode, and there is plan to eliminate this hard dependency. As for Fabric components, i.e. peer/orderer, it's just a process and you can run it however you want. Docker just helps developer to set up environment with ease (one can just pull images and run).
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Is anyone done Hyperledger fabric multi org in multi host using docker compose file.
I just need to know the feasibility, if possible please share the reference material as well.
I am also tried with the docker compose commands as mentioned in this link https://medium.com/#wahabjawed/hyperledger-fabric-on-multiple-hosts-a33b08ef24f
It is very well feasible and we have tried it out.
There are two ways you can achieve
1. Either docker-compose up with splitting the files or passing arguments as params where each org has to be brought up
2. Using stack deploy for a single file and keeping the constraints as per the schema 3.5 for docker compose file.
Rest all process remains the same.
You need to use docker swarm init to initialise the cluster and using the token generated add other VMs. Refer docker swarm guide for help.
I have tried to search and research on this topic, but could not find any solution so far.
Has anyone tried this scenario? Start the fabric, create a business network, create a sample app to post transactions to this network. So far so good. Shut down the fabric now and restart it. Has anyone seen that the transactions are lost? So how does one go about making the ledger survive restarts?
You need to mount a volume for the directory /var/hyperledger/production in the orderer and peer containers in docker. This is where all the persistent data is being held containing channel information, transactions and blocks.
If you are spinning up your containers through docker-compose you can add:
volumes:
- <some local dir>:/var/hyperledger/production
If you are spinning up your containers through docker run add the argument:
-v <some local dir>:/var/hyperledger/production
Haven't used composer much myself so not quite sure how composer builds the containers, if you are using that.
You will also need to make sure each node goes to its own directory so it doesn't conflict.
I have successfully installed a few hyperledger demos, including the marbles one (https://github.com/IBM-Blockchain/marbles)
A few questions,
How can I move some of the marbles demo nodes to another host/s and still get this demo to work?
I have read the following two posts on the same topic already (where
docker-swarm has been used for intra-host communication)
How can I set up hyperledger fabric with multiple hosts using Docker?
hyperledger-fabric-with-multiple-hosts-using-docker &
How can I make a communication between several docker containers on my local network
communication-between-several-docker-containers-on-my-local-net
I still couldn't decipher installing additional nodes and running them
on different hosts.
As running blockchain nodes on multiple hosts seems to be a common task,
how is it being done now? I saw references to Cello and an ansible
script, though they look not so mature and sure shot solutions.
Could I install the fabric nodes manually by pulling the hyperledger/fabric peer images from the docker hub? How do I then install & run the marbles demo on this pulled images?
Thanks
How can I move some of the marbles demo nodes to another host/s and still get this demo to work?
What do you want to do? I don't understand why you want to move a node. Has it got any sense? If you move some nodes, you are removing them from your Blockchain. If they are part of the Ordering Service or they endorsement is required for the endorsement policy, your demo will not continue running.
The intra-host communication and the communication among multiple docker containers are different things from what you are asking.
Could I install the fabric nodes manually by pulling the
hyperledger/fabric peer images from the docker hub? How do I then
install & run the marbles demo on this pulled images?
You can install you nodes manually via the docker-compose. You should define what you want to start up and then execute it. Of course, you should have in your machine the corresponding docker images. Then, you should deploy the marbles Smart Contract in your peers. You have more info about it here.
I was able to setup Hyperledger Composer on Docker containers on a mac by following the instructions here: https://hyperledger.github.io/composer/installing/development-tools.html. I was also able to develop a proof of concept project with both a mobile web app that connected the blockchain via a rest API.
Now, I am trying to run the nodes on actual Ubuntu servers in a local network but I can't seem to find any tutorial to explains how to do that.
I know I might have some gap in my knowledge of computer architecture or networking in general that's why I am struggling with this.
I was looking at the downloadFabric.sh script in fabric-tools and I see how the Docker images are filled. I was thinking maybe I should just pull the Docker images to the individual Linux servers.
### Pull and tag the latest Hyperledger Fabric base image.
docker pull hyperledger/fabric-peer:$ARCH-1.0.1 on server 1
docker pull hyperledger/fabric-ca:$ARCH-1.0.1 on server 2
docker pull hyperledger/fabric-ccenv:$ARCH-1.0.1 on server 3
docker pull hyperledger/fabric-orderer:$ARCH-1.0.1
docker pull hyperledger/fabric-couchdb:$ARCH-1.0.1
and so on.
Please, how will you do this? Are there any resources I missed while researching how to do this? Can you point me to some resources that I can read to help understand how to do this?
So Hyperledger Composer will connect to the Fabric that you configure. So your problem is to configure a Fabric environment and set of nodes, using the host name resolution etc that you want to configure your network.
Would advise to check out the Fabric Docs http://hyperledger-fabric.readthedocs.io/en/latest/build_network.html to build your network. They have some sample-networks (see the Github Repository here -> https://github.com/hyperledger/fabric/tree/release/examples )
The 'Fabric' that is set up by Hyperledger Composer's dev environment is just a Dev environment with one peer configured (via docker containers) to get you going.
You need to understand from the Fabric Docs how to set up your network, then come back to Composer (once all that is set up) and use connection profiles to connect to the runtime Fabric.
You could consider using docker-composer which builds on the docker client and makes it easier to run multiple docker containers. Please consult the manual to install docker-compose.
After installing docker-compose, you can use the startFabric.sh script provided here to start Fabric containers you had downloaded.
You may want to consider deploying Fabric with it's sister project Hyperledger Cello. Specifically, the Ansible driver for Kubernetes.
The samples provided in both Composer and Fabric are mostly for single host deployment. You could adapt the Docker Compose to use Swarm, but even Docker is moving away from Swarm, now.
Of course, if you just want to try to run locally, then the Build Your First Network tutorial in Hyperledger Fabric will get you rolling with the docker images in your question.
I have been working on hyperledger-fabric node sdk v 1.0 and successfully created prototype based on dockers . However now I wanted to implement this architecture on real systems. I haven't found any documentation which helps in setting up environment in real systems. All I found is to set up different peers and organization using dockers and then invoke transactions etc.Can we connect different computer machines using dockers and then spin up the network on all these different machine to create private blockchain?
Yes, you can do it. For that, first of all you should define your network configuration. Then, you would create the artifacts that are required for the network: the keys, the channel artifact, the genesis block... You would follow the steps that are defined on the Fabric documentation to Build your first network. Also, you should share the public keys and the genesis block.
Then, in each machine you would install the docker images, like is explained in the Fabric documentation. After that, you would define the containers that you are going to set up in each machine. You do that on the docker configuration files (docker-compose.yaml, docker-base.yaml...). There, be aware of defining well the docker network configuration. You have more info about it in the answer of this question.
At the end you would switch on each container executin the docker-compose.
I don't know if I've given you enough information. If not, ask again please.
Docker is good for production systems. Docker swarm can be used for connecting multiple machines.