I started a new composer network (two org setup), i.e. a second chaincode (one was already installed and running). I installed it and while starting, couple of chaincode containers were stuck while downloading node modules, and the command to start chaincode was timed out. To start again I removed the chaincode containers and tried to start again. But I am getting error : status: 500, message: chaincode exists.
That message from hyperledger fabric means that the chaincode has already been instantiated, so you do not need to invoke composer network start again. Any request you send to a peer will try to bring up a chaincode container to process that request if there isn't one already started.
composer network start sends the instantiate transaction to peers and as such the peers need to simulate the request proposal and to do that it needs a chaincode container so goes through the process of creating a chaincode container image and chaincode container to execute the request (but any transaction proposal causes the same process to be followed). So long as the instantiation policy is satisfied (and the default I believe is for 1 successful instantiation proposal) then the chaincode is then defined as instantiated.
Related
What happens during chaincode install and instantiate in Hyperledger fabric?
A common misunderstanding when interacting with chaincode on the network is the difference between chaincode installation and instantiation. It is important that all peers on the network MUST have chaincode installed, but not instantiated.
Chaincode installation means that we are putting the source code (of our chaincode) on a specific peer.
Chaincode instantiation means that we are initializing the chaincode source code. This is done by passing through a set of initialization arguments attached to the instantiate command.
Please note that, even though the chaincode is installed on the peer, when chaincode gets instantiated, it is instantiated on the channel.
Chaincode installation means keeping chaincode on the peers of the ledger.
chaincode instantiation means initializing chaincode with the set of parameters with we pass through chaincode command.
Installing the chaincode on the peers is required and instantiating the chaincode is not necessary.
Install:
The process of placing a chaincode on a peer’s file system.
Instantiate:
The process of starting and initializing a chaincode application on a specific channel. After instantiation, peers that have the chaincode installed can accept chaincode invocations. As it's related to channel, you do not need to instantiate from every peer on this channel, once it's instantiate by maintaining some valid process, the rules will be same for each participating node.
NOTE: This method i.e. Instantiate was used in the 1.4.x and older versions of the chaincode lifecycle. For the current procedure used to start a chaincode on a channel with the new Fabric chaincode lifecycle introduced as part of Fabric v2.0, see Chaincode-definition_.
So from Fabric v2.0 or later, you have to commit the chaincode after proper approval process instead of Instantiate.
What steps are required in order to add an endorsing peer to a blockchain network (in hyperledger-fabric)? What about promoting a committing peer in an endorsing one?
Should I just alter files crypto-config.yaml and configtx.yaml by adding the new peer?
I am using the fabcar example from the fabric-samples repo (https://github.com/hyperledger/fabric-samples), so should I change the docker-compose(-cli).yaml also? When starting the network with startFabric.sh script, should I just install chaincode on the new peers, or are other steps requires also?
I tried it with just installing a chaincode on the new peers, however I got an error stating that "... Consortium was not met when instantiating the chaincode ..."
Edit:
I was able to install the chaincode on all four peers and instantiate it on the channel. Initial non-query transaction is successful and another one after it. However, after the first two transactions I get:
Failed to submit transaction createInquiry: Error: Peer localhost:8051 has rejected transaction "e8a83c12bfbcae97c7a3f2baaad7735fe8b44195a0ce252a3533a7b4a2a8103b" with code "ENDORSEMENT_POLICY_FAILURE"
can you stop, remove and kill containers and try once again to instantiate.
what are the steps to troubleshoot below error when trying to invoke a chaincode?
Error: could not assemble transaction: ProposalResponsePayloads do not match - proposal response: version:1 response:<status:200 payload:"[\"00000\"]" > ...
we get this error when trying to invoke a chaincode using peer chaincode invoke
#morpheus: Has answered it excellently:
So I thought I will add to the above list of possible reasons:
I had by mistake added something like getting the current timestamp, and was using this for capturing the event date. This led to the different transaction responses by the endorsers, thus leading to the Response Payload not matching. The whole point to remember is that the result of execution should be deterministic as it is going to be run on all of the selected endorsing peers.
So use ctx.GetStub().GetTxTimestamp() for capturing the event time. This is the time when the transaction began and it will be constant across the endorser executions.
Check that you have installed the chaincode on all the peers your peer chaincode invoke command is targetting. That is the most likely cause of this error.
Other ways this error can occur:
You modified your chaincode and instead of installing a new version and upgrading the chaincode, you tried to be smart and overwrite the chaincode with the new file thinking that Fabric would not notice.
It can also happen if there is no chaincode container running on target peer and Docker daemon cannot be found on the peer node when it tries to instantiate a container or instantiation fails for some other reason
Another reason why this error can happen is if some peer nodes are using LevelDB and others are using CouchDB
The error itself originates from here. The first step to debug this error is to invoke the chaincode individually one-by-one on one peer node at a time.
Another reason that I forgot to check is using storing randomly generated values.
I never used random "Id" until now and didn't notice that it leads to ENDORSEMENT_MISMATCH
In the hyperledger fabric documentation, there are 2 terms used
1. Install the chaincode on peers and
2. Instantiate the chaincode on the channel
What are the major differences between these two?
In the documentation it said that a chaincode can be installed on multiple peers but can be instantiated once. I understood this point as a channel only needs the information about the channel.
I was following the balance-transfer example, so after channel creation, peers need to be joined to that channel.
There are 2 peers which joined the channel ["peer0.org1.example.com", "peer0.org1.example.com"], so when I am instantiating the chaincode it is creating 2 docker images of chaincode
dev-peer0.org1.example.com-chaincode-v0
dev-peer1.org1.example.com-chaincode-v0
What these 2 images really mean?
Isn't initializing the chaincode means for the channel?
Or channel initialize it on all the peers who joined it?
Where actually this initialization is happening?
Thanks!
Thanks to #PaulO'Mahony and #kajuken for the resources and explanation.
Following are the summary of my doubts:
A chaincode runs in a Docker container that is associated with any peer that needs to interact with it.
Chaincode is installed on a peer, then instantiated on a channel.
All members that want to submit transactions or read data by using a chaincode need to install the chaincode on their peer.
Instantiation will input the initial data used by the chaincode, and then start the chaincode containers on peers joined to the channel with the chaincode installed.
Note that only one network member needs to instantiate a chaincode. If a peer with a chaincode installed joins a channel where it has already been instantiated, the chaincode container will start automatically.
a chaincode is installed onto the file system of every peer that joins a channel, the chaincode must then be instantiated on the channel so that peers can interact with the ledger via the chaincode container. The instantiation performs any necessary initialization of the chaincode. This will often involve setting the key value pairs that comprise a chaincode's initial world state.
A peer can the install the chaincode once, and then use the same chaincode container on any channel where it has been instantiated.
References:
install and instantiate the chaincode
instantiate the chaincode
What these 2 images really mean?
Isn't initializing the chaincode means for the channel?
Yes and no. Every peer needs the same version of the chaincode installed on itself since everybody needs to be able to execute and verify incoming queries/invokes.
So there are 2 steps to do.
install the chaincode on every peer on the channel
instantiate the chaincode on the channel
Where actually this initialization is happening?
So the instantiating of chaincode is happening last after every peer has "knowledge" of the chaincode and it can be verified.
I have a question about chaincode instantiation.
I think all same chaincode in a channel will be instantiated all at once by one request from this doc.
http://hyperledger-fabric.readthedocs.io/en/release-1.1/install_instantiate.html
Note: The initial instantiation applies to all peers in the channel, and is affected upon any peer that has the chaincode installed.
but in my vagrant environment with v1.0.6 fabric, always only one (of three installed cc on endorsers) chaincode is instantiated by my Instantiate request from Node SDK.
then it seems that if any other proposal request is received, that endorser start to instantiate other chaincode. so if my endorsement policy needs that endorsement, first invoke request is failed...
Initially, chaincode will only be launched on peers to which you send the actual instantiate proposal. It will then be launched on other peers in the channel upon the first invoke request. If you want to have the chaincode launched at instantiate time, you need to send the instantiate request to all of the endorsing peers. The channel.sendInstantiateProposal takes a ChaincodeInstantiateUpgradeRequest which allows you to specify an array of peers in it's target property.