MultiChain Developer Q&A - Recent questions tagged wallet

second server with same(persistent) waller address

Fri, 21 Jan 2022 15:57:57 +0000

Hi

In this tutorial: https://www.multicchain.com/getting-started/ we have this command: multichaind chain1@[ip-address]:[port]
If I restart the sencond server several times and execute the previous command, a new wallet address is always generated.

Is it possible to start the second server and always use the same address?
That is, I don't want the second server to keep generating new wallet addresses on each connection, is it possible for the second server to always use the same wallet address?

thanks

This wallet contains no addresses with permission to this stream and global send permission.

Mon, 31 May 2021 12:23:33 +0000

Hello, We are using 10 nodes and permissions to all 10 nodes have been granted through same way. 9/10 nodes are working properly. Even though connect, send, receive and write to stream permissions are granted on 10th node, when we perform a transaction from that particular node, we got the error: This wallet contains no addresses with permission to this stream and global send permission. Kindly let us know the appropriate solution. As we are following the same procedure mentioned on your documentation and 9 out of 10 nodes are working fine. But on each day, any node out of 10 nodes stops working and throws this error. And we delete that node, reconnect it , but the same error occurs.

how to upgrade stream filters code? And how to delete existing filter?

Wed, 15 Apr 2020 14:04:29 +0000

how to update filters code which is already created and s there any way to delete the filter?

Please Provide Example of 4 steps of "To use an approval" of transaction-filter github code: To use an approval"

Sat, 21 Mar 2020 10:30:32 +0000

Sir the ways you mentioned are not helpful

Referer this code:

https://github.com/MultiChain/smart-filter-examples/blob/master/transaction-filters/approve-asset-transfer.js

Here they have mentioned steps "to use an approval" in which the commands which are mentioned are:

createrawsendfrom and appendrawtransaction, there is no syntax given in any links provided by multichain and the links which you have mentioned in my previous question.

You may say the other commands are similar so I should refer that, so I would like to tell you that I have already referred and tried executing that and accordingly I also tried above commands but I'm facing syntax issue that is why I wanted proper guidance. If you could provide me that 4 steps example with syntax then I would really appreciate it.

Can you please provide me an example of "To use an approval" steps:

Thu, 19 Mar 2020 16:45:32 +0000

Can you please give me an example of those 4 steps?? I know the commands are given but if any demo example you can give consisting of those 4 steps would be really helpful for me. Please I request you.

In that code link it is said that first, we need to send approval, so please provide me the example where you first send approval using "sendfrom" command and then those 4 steps.
Sender address you can take :1KB85GgVgHE8fw6tMMeQ7DYS9fkY192yk8uy1V
Receiver address you can take :1MB85GgVgHE8fw6tMMeQ7DYS9fkY192yk8uy1V

wallet gets damaged

Tue, 05 Nov 2019 08:03:08 +0000

Dear tech team,

I'm developing an application with MC and I wish to delivery my customer a cold wallet saved in crypto hw usb. My customer uses the crypto usb opening it and running the cold wallet so that my application can access the wallet through a socket in order to get new addresses, signing and so on.

Everything works fine but the crypto key has a timeout so that after a while it locks the hw. In such case when I try to open the wallet I got the following issue:

corruption: checksum mismatch

I try to run the wallet with -reindex=1 option but it doesn't solve so I have to install it again.

Unfortunately I can't disable the lock timeout of the crypto key and it is a security feature my customer ask.

Can you suggest a way out?

Thanks for your support

Not address existing wallet but with desired permissions is able to issue asset

Mon, 14 Oct 2019 09:16:31 +0000

With the help of admin permission I have tried to create an asset with the issues address(which does not belong to my wallet but have receive & issue permission).I am thinking that this should generate an error as the issuing address does not belong to my account/wallet but I found that the asset has successfully created and within other nodes, it is also visible. Please help me out to understand why does the error is not produced.

Is there sensitive data in the /wallet directory?

Fri, 13 Sep 2019 20:24:45 +0000

Is all sensitive information (i.e., private keys) contained in the wallet.dat file, and the wallet dir is only stuff like pub keys & watch only addresses? Or is there sensitive info in the folder files also?

I'm looking at backup & restore procedures, and want to make sure I understand what file(s) I should be most paranoid about.

Thanks,

-Tom

How to generate private key based on user data in multichain?

Wed, 12 Jun 2019 07:31:24 +0000

Hello Team,

I have requirement of generating keypairs based on user information in multichain.
This requirement is beacuse of following problems:
1)If user forget his/her private key then how to retrieve.
2)how to retrieve user old account if user forgets key.

Thanks & Regards,

Khetesh Rotangan

Is that possible to recover the pub/private key in multichain.?

Mon, 10 Jun 2019 11:23:10 +0000

1. We generating the address, public and private key for users to create wallet. In our application we using the signed transactions using private key. What will happen if user lost the private key. How to recover it.?

is there any function to recover it?

2. Is that possible to generate the pub/pri keys using the users details.?

Please can you tell me the benefit of a cold node

Thu, 02 May 2019 14:43:21 +0000

I understand that the multichain cold node is for offline purpose in a blockchain but how does it contribute to the blockchain in any way if its offline by not participating in consensus or mining etc. What is its benefit?

Can a node which does not have private key stored in own wallet

Thu, 02 May 2019 14:41:45 +0000

Can a node which does not have private key stored in own wallet but in an external Hardware Security Module be able to mine,admin or behave normal as other nodes?

how to manage node in blockchains for multi chain platform?

Wed, 20 Mar 2019 12:10:15 +0000

Electrum support: is it foreseen to integrate multichain with the electrum wallet in the future? (https://electrum.org)

Fri, 15 Mar 2019 15:49:50 +0000

Import single wallet

Wed, 06 Feb 2019 18:24:26 +0000

Hi,

can I import a single built-in wallet (privkey + address) in some running node with an existing wallet.dat?

Thank you very much

how to create a node which can connect to an existing node .

Tue, 05 Feb 2019 17:51:26 +0000

how to create a node which can connect to an existing node . I want all the nodes to sync at the same time and all transactions should be present on all the nodes. In order to create a cluster of nodes for better reliability.

Can you tell me how to clone a node and how two nodes will communicate to each other.?

Scope and use cases for addresses (and not key pairs)

Thu, 17 Jan 2019 18:33:12 +0000

Hi,

I'm a newbie to Multichain and I'm trying to understand how everything fits in terms of users. Let me explain.

Typically in an application, security is defined by authentication and authorization. Authentication is about users and their passwords (to be simplistic), and authorization is about what an already authenticated user can do or cannot. These are basic security concepts.

If I try to extrapolate such concepts to Multichain, this is where I need some help to fit them properly, so please correct me if I'm mistaken.

As far as I understand Multichain, there are two types of authentication:

At the node level --> Where you can configure whether anyone can join (public blockchain) or they need to be granted access (private blockchain).
At the wallet level --> Where you get an address and can start running actions against the blockchain (based on your permissions, of course).

While the former seems pretty clear to me, the latter poses some doubts:

If I get an address in a node, and permissions for whatever actions, then such address becomes both the username and the password because I just need to indicate it when running commands like publishing or subscribing to a stream; in other words, I don't need to sign anything or use any private key (which is not even visible when you create a new address with 'getnewaddress') and just the address is enough. Is my understanding correct?
So if I just need the address, isn't this a security issue as anyone who finds it out can impersonate me?
Therefore, when using 'getnewaddress', is such address actually becoming sort of the "do not share, do not disclose" information, similarly to a private key?

My confusion here is basically that I've been playing around with public test blockchains in the past (Ethereum, Bitcoin) and when creating a wallet (i.e. an address in the scope of Multichain), I was given also the private key, so whenever I wanted to send a transaction, I had to use my wallet address, but always sign it with my private key. However, in Multichain you would only need the wallet address.

Now sure if I'm exposing my concerns properly here, but I would like to really understand what the use cases are for addresses created with 'getnewaddress'.

Also reading the docs I've found a reference in 'getnewaddress' to a parameter 'accounts', but I haven't been able to find any documentation around it. Could you also please elaborate a bit more on this?

Thanks!

sendrawtransaction giving error code -26

Fri, 28 Dec 2018 09:54:56 +0000

While sending the final signed hex to the sendrawtransaction API it outputs me this error message with error code 26:

16: ConnectInputs failed: mandatory-script-verify-flag-failed (Script evaluated without error but finished with a false/empty top stack element) can someone explain me why I am not getting final transaction id instead of this error message?

Why is wallet folder size large in contrast to blocks folder?

Fri, 21 Dec 2018 13:26:32 +0000

Hello,

We are running tests to determine per-node storage requirements with:

- 2 Nodes

- Publishing items (key-values) to a stream (Not Subscribed)

Observations:

Change in file size after publishing 1 item to a stream in 1 block
Change in size of ./Blocks folder	3409 bytes
Change in size of ./Wallet folder	4492 bytes

Change in file size after publishing 10 items to a stream in 1 block
Change in size of ./Blocks folder	3839 bytes
Change in size of ./Wallet folder	18576 bytes

Change in file size after publishing 100 items to a stream in 1 block
Change in size of ./Blocks folder	7732 bytes
Change in size of ./Wallet folder	187561 bytes

Note: Publishing one item corresponds to one transaction on-chain.

Questions:

Q1: Why does the node wallet that created the item store such large amount of data in contrast to blocks folder? Even though we have not subscribed to the stream!

Q2: Does Multichain have an option of not storing transactions in wallet? (This is because we are indexing and keeping the reference to on-chain transactions in an external off-chain database)

Thank you !

How are public keys stored in a wallet?

Wed, 12 Dec 2018 07:54:37 +0000

Hello,

I have a multiple questions about how MC stores addresses in the wallet:

1. Are public address are encrypted before being save in a wallet? or does anyone with physical access to the node can view the addresses.

2. If the wallet folder is cleared inside the node, would the node's wallet be emptied and would continue to work? or would it crash and stop working? because in other blockchain, you can just clear your wallet if necessary by just deleting the keystores.

Thanks in advance, and keep up the good work!

Can you stop a node from storing private keys in it's wallet?

Tue, 11 Dec 2018 08:20:19 +0000

If anyone-can-connect is set true to create a public blockchain, a node owner can maliciously generate and store private keys on the node and then provide them to users.

I was wondering if there is a way to either limit the capability of nodes to create addresses or to remove the capability to store private keys in the wallet

Parallel request to sendRawTransactionfrom api got failed

Mon, 10 Dec 2018 16:54:20 +0000

I have a blockchain node and one app server connected to that node. I tried to perform stress testing using Apache JMeter tool. so I fired 100 requests in parallel to my app server's API which in turn calls createRawSendFrom API of the node. the job of the API to save some data in the stream. when I made 100 requests all the request was successful with the txn_id in response. but when I picked up one of the txn_id and called get wallet txn_id API it returned "invalid txn_id" and also data was not saved in the stream for that particular API call.

My assumption is- createRawSendFrom api is based on "coin selection algorithm" to get the input from the unspent output. so do I need enough number of unspent output (in my case 100)

Has the admin got access to see other wallet/address transaction?

Wed, 05 Dec 2018 09:05:34 +0000

Hi Multichain,
I wanted to know if Multichain allows the Address with ADMIN permissions, see the the transaction history of created and validated address/wallet with limited permissions?

Note: The address can be created by any one of the main server nodes in the Consortium network.

Can I revoke access for an address in a node to view items in a stream

Sat, 01 Dec 2018 09:30:25 +0000

Dear all,

I want to create a stream- stream1 , say suppose by an address label x1 , i want to grant a limited time permission to address label x2 to view the items in stream1 , now can i create a workflow for x1 to grant or revoke permission to x2 ? , i have checked the api commands which revokes the access for address to block chain (like create , connect , send , receive ..etc) but can it be done stream wise??

both the address would be on same node

Multichain in-node wallet adresses performance

Fri, 16 Nov 2018 15:00:29 +0000

Hello,

We are currently developing an application in Python (Django) using Multichain to control all the transaction and currency related user information.

The transactions we make are pretty simple: getnewaddress, grant, issuemore, getaddressbalances and sendassetfrom. Everything is working fine, however, we have experienced a serious slow down in the response time when increasing the number of adresses in the chain.

To give some numbers we have developed a set of unit tests with the basic functionality of the application:

Tests completion time without multichain implementation: 80s-100s
Tests completion time with multichain implemented and 1000 adresses in the wallet: 120s-150s
Tests completion time with multichain implemented and 60k adresses in the wallet: 800s-1000s

Note that these are the same tests just varying the amount of adresses in the wallet.

Right now we just have one node with all the addresses. What's the maximum addresses a node can hold without degrading its performance? Is it the same as if the adresses were watch only (no private keys in the node)? What's the right architecture to support massive numbers of addresses?

Thank you very much for your time.

how to import the whole wallet with all addresses and transactions in a new chain ?

Fri, 19 Oct 2018 09:36:59 +0000

I am running a multichain node and for security purpose i want to run another multichain node to be exact replica of this node so that i don't loose the addresses and their tokens in case anyone accesses my node and stops it.

I have encrypted a running node's wallet - node stop syncing

Wed, 17 Oct 2018 13:30:32 +0000

Hi,

I have encrypted a running node's wallet (encryptwallet) and now the node is stop syncing with the network.

The debug messages are:

2018-10-17 13:23:59 mchn: Sending minimal parameter set to xx.xx.xx.xx:yyyy
2018-10-17 13:23:59 mchn: Internal error: Connection address not found in the wallet
2018-10-17 13:23:59 receive version message: /MultiChain:0.1.0.9/: version 70002, blocks=85076, us=my.ip.address:49969, peer=545
2018-10-17 13:23:59 mchn: Internal error: Connection address not found in the wallet
2018-10-17 13:23:59 ProcessMessage(verack, 321 bytes) FAILED peer=545

getinfo:

{
"version" : "1.0.6",
"nodeversion" : 10006901,
"protocolversion" : 10009,
"chainname" : "CHAN1",
"description" : "...",
"protocol" : "multichain",
"port" : yyyy,
"setupblocks" : 60,
"nodeaddress" : "CHAN1@192.168.100.11:7269",
"burnaddress" : "fXXXXXXY1mXXXXXXtNXXXXXXYJXXXXXXbMXyzT",
"incomingpaused" : false,
"miningpaused" : false,
"walletversion" : 60000,
"balance" : 0.00000000,
"walletdbversion" : 2,
"reindex" : false,
"blocks" : 85025,
"timeoffset" : 0,
"connections" : 0,
"proxy" : "",
"difficulty" : 0.00000006,
"testnet" : false,
"keypoololdest" : 1539779127,
"keypoolsize" : 1,
"unlocked_until" : 0,
"paytxfee" : 0.00000000,
"relayfee" : 0.00000000,
"errors" : ""
}

It is stop working at that block height (when I encrypted the wallet), the network height now is 85076

Can you grab the wallet address of the second server without first having to connect to a chain?

Mon, 24 Sep 2018 20:41:46 +0000

Hello,

In the 'Getting Started' guide, 2. Connecting to a blockchain states that after the second server runs multichaind chain1@[ip-address]:[port], you'll be shown a message containing an address in the node's wallet.

1. Is there anywhere else we can get the node's wallet address, without having to try to connect to a chain? The api commands I see all require something like multichain-cli [chain name] getaddresses

2. Out of curiosity, is the node's wallet address the server's public key?

Thank you!

One question on Multi-sig, Can we add also one key called master signature that alone can unlock transaction?

Fri, 21 Sep 2018 09:45:59 +0000

One question on Multi-sig, We know it works if 2 signature are given Can we add also a 3rd one called master signature that alone can unlock transaction? This key should be known only by me ?

How to do a modular development on multichain for end user

Wed, 12 Sep 2018 19:02:55 +0000

Hi, I am following multichain from quite some time. Now , I am planning to develop/design one application based on it. I understand that

1) There can be multiple nodes doing transactions in a permissioned/private blockchain

2) Each node can have a UI developed on any technology , which can act as a wallet to publish/receive transaction or a block explorer to search transactions

3) Authentication/Authorisation on this UI has to build locally to control access and action

Is there a way I can setup these things quickly for any newly connected node ? Or any thought on how should I go about this ?

thanks

Amar

asset with publick-private key

Mon, 03 Sep 2018 07:36:53 +0000

We develop APP wallet to access a kind of token implemented in multichain asset

as a base for the exchange of all other assets.

Multichain asset is implemented in the permission based on the node address

(like the command grant 1... send,receive )

It seems not like the native coin, using private key to protect their properties.

Are there any solutions to add the private key into the assets ??

==>

i think i got it and made wrong concepts before.

many thanks

Can not get all list wallet addresses

Thu, 30 Aug 2018 09:05:01 +0000

Hello,

I have a question when I call: getaddresses in Multichain.

I have 2 nodes multichain. (2 nodes are running)

In the Node 1, I back up file: "wallet.dat" and folder: "wallet" and I restore it to Node 2.

In the Node 2, I call function: "getaddresses", but when I check list address in Node 2. It's old addresses and different list wallet address in node 1.

I have to stop and re-start multichain node 2. Then, I check list wallet address again. It's updated and same with list wallet addresses in Node 1.

So, How to update the wallet address list in node 2 without restart multichain in Node 2?

pls help me,

thank you so much.

how can shown a message containing an address in this node’s wallet for blockchain???

Wed, 25 Jul 2018 04:25:54 +0000

Clustering Multichain nodes

Mon, 25 Jun 2018 09:01:57 +0000

Hi, I'm researching about Mutlichain. I want to setup 2 cluster multichain Nodes. It will auto share wallet address when I import a wallet address to a multichain node. (I will not import the private key of wallet address to the Multichain node)

Could you please help me to setup it?

Thank you.

How to derive public key of wallet address?

Thu, 14 Jun 2018 12:42:13 +0000

Hi,

How can I get the public key for a wallet address? The purpose is I want to encrypt something using the recipient's public key which he can presumably decrypt since he has his private key.

I can see that getaddresses api call with verbose=true shows the pubkey for each address, but this is only for addresses stored in the current node's wallet. What if the address is from another node?

Thanks

How do you pass the node's wallet address to a master node in order to grant permission to this new node

Wed, 06 Jun 2018 08:55:43 +0000

Hello, I'm facing a problem

All the usage of Multichain when all node are well configured is fine.

But every time when a new node join the network, we need to grant some permissions needed by this new node. How do you do this process offchain ?

(on the getting started :

"Back on the first server, add connection permissions for this address:

multichain-cli chain1 grant wallet_adress connect"

If we configure the chain with anyone-can-* we are facing the

No unspent outputs are available problem and we can solve this by some other node sending

a zero quantity but this operation need the wallet address )

Do you pass this address by mail ? SMS ? delivery boy ? CTRL + C CTRL + V ? Is there a specific workflow to garanty this address ?

Cordially

Can we replace the node's default wallet with an imported wallet public/private key?

Fri, 01 Jun 2018 22:15:15 +0000

Hi,

I understand that when you start a multichain node, it has a default wallet automatically created, and this wallet is used for the node's mining and other transactions. We would like the default wallet address account's to use a private/public key generated externally and imported into the wallet.

Would this be possible?

Thanks

What algorithm is used to create wallets and key pairs

Tue, 29 May 2018 20:37:58 +0000

Dear Multichain team

1) What algorithm is used to generate wallets? Are the wallets provides by a third party?

2) How do I receive my private key to my own wallet?

3) once received, do I have to back it up or do you store it for me?

4) Do I need the private key every time I sign in or when do I use it?

4) I understand that once I send a transaction, I send it to the other nodes adress. Is the adress therefore the public key!

signRawTransaction is not signining

Mon, 28 May 2018 08:57:33 +0000

I have 2 of 2 multisig address and the private key of those address stored in wallet. i have created an asset using that multisig address.

now i want to issue the asset from multisig address to other address but using raw transaction.

here i want two different person(belongs to multisig address) to sign it separately on their own.

so i performed following step-

createrawsendfrom 4GUoGwLmqG6BeTE8dx2DWTWCqKbrCfN7uYtypF '{"1PpwB7YosnV3p9nqqn9Uoic4C3aC8KCfkS84am":{"asset9":500}}' '[]' ''

i get hex from the first operation

signrawtransaction hex [privateKey1]

signrawtransaction hex [privateKey2]

i am getting {hex:'some random hex',complete:false}

why i am getting {complete:false} everytime i sign ?

should i keep the private keys inside the wallet or outside ?

Fri, 11 May 2018 06:19:24 +0000

should i really save the private key of users outside of the wallet?

I have setup 4 multichain node on digital ocean server talking to each other. so my question is should i really be worried about of instances getting compromised. even if i save the private key of users on another server of digital ocean that can also be compromised. isn't it ? so what do you guys suggest ?

how can i use walletnotify command to get notification

Tue, 08 May 2018 06:45:35 +0000

Hi,

Could you please give me an example of how to set this runtime param to get notification everytime a new item appended in a stream called stream9 and where can i see all the notifications. how can i call external services when one of these notification occurs

i tried following

multichain-cli chain1 walletnotify %e streamcreationId // i got method not found

multichaind -walletnotify %e streamcreationId -daemon // it didn't show any error

what is the type of built-in wallet deterministic wallet or nondeterministic wallet ?

Mon, 16 Apr 2018 19:03:55 +0000

also I need to know if there is any way to make addresses globally identified in each node once the creation rather than identified in only the node where I create it and import address one by one in each node ?

Node, Wallet and Addresses

Mon, 16 Apr 2018 06:57:38 +0000

How exactly is Node and Wallet linked to each other? (Please answer with respect to Addresses)

Move address from one node to another

Fri, 13 Apr 2018 17:14:20 +0000

I know it is not possible to 'remove' an address to retain referential integrity. and not advisable to have multiple nodes know the private keys of an address....

so... how could we 'move' an address from one node to another:

Could we:
a: Export private and public keys for an address on node1
b: Import private and public keys for an address on node2
c: Remove the private key for an address on node1 (thus making the address 'watch only' on node1)

Multichain addresses

Thu, 12 Apr 2018 12:53:11 +0000

I appreciate your great efforts by providing us the platform to learn more about blockchain and also constant support on this forum.

I require answer for two questions:
1. I am curious to know if every address needs to be connected to the node in a private network?
2. Is it possible to generate address outside the private network as a peer and transact? (Like Metamask)

Can I search all transactions done by an address that is not in my wallet?

Mon, 09 Apr 2018 11:05:14 +0000

Hi,

I am trying to build something using multichain. What I need is a way to query the blockchain and return all the transactions done by an address. I am not using streams. I am using a Bitcoin style blockchain.

Best option to store user confidential Info ?

Wed, 21 Mar 2018 10:23:28 +0000

Hi Multichain Team,

what is the best way to store users confidential info in multichiain. Actully I want to register users info like email, password etc then verify user to login into the application. Then those users can add there addresses and make transactions on those addresses.

Option one is Streams for Users and user addresses (user can have one or more addresses). Is streams data confidential if other nodes not subscribed.

Multiple chains to store this data or any thing which is best to store users confidential info in blockchain.

Thanks

Node Backup

Wed, 21 Mar 2018 00:37:26 +0000

Is it possible to backup the node and transfer it to another machine?

Like just copy the node file and transfer it to another PC. Is this possible??

My concern is that in a scenario when we need to upgrade all the node machines and the chain will

be stopped for a while, we want to backup the chain and run it new the machines. Then after we restore the

chain the data will still be there as if nothing has happen.

Multi permissions required

Thu, 15 Mar 2018 02:30:20 +0000

Is it possible to issue an asset but it needs 2 or more nodes/server to approve the asset.

I'm thinking that there two or more nodes in the blockchain that will need to approve first the assets before being issued or increase the amount/qty of assets.

External key management

Wed, 14 Mar 2018 03:03:17 +0000

I tried the guide for external key management. And I have a questions in mind for it.

Can we just deploy one node of Multichain and use External Key for other users to transact?

I'm trying to implement by using one Server node (or more) and some users will be just using external key to access the Blockchain. Is that possible?