I have setup one bitcoin core node on machine A, and one bitcoin core node on machine B. The two machines can ping each other.

On machine A (10.0.0.11):
bitcoind -regtest -port=18332 -rpcport=8331
Bitcoin server starting

On machine B (11.0.0.12):
bitcoind -regtest -port=18332 -rpcport=8331 -connect=10.0.0.11:18332
Bitcoin server starting

Then on machine B, i run the command:
"bitcoin-cli -regtest  -port=18332 -rpcport=8331 getconnectioncount"

It returns 0. Is there any mistakes in my steps ?

When i run a bitcoin core node in testnet, how do i mine bitcoin in testnet? What is the settings in bitcoin.conf ? 

The setgenerate is not working, see below:
./bitcoin-cli -testnet setgenerate true

Thanks. What is the disk space that is needed to run testnet? According to https://bitcoin.org/en/bitcoin-core/features/requirements  , it is 145 GB disk space for mainnet.

https://en.bitcoin.it/wiki/Testnet  , it is 14 GB for testnet.

Thank you !! I am a beginner in bitcoin, the forum helps a lot.

From bitcoin core:

ubuntu@ip-172-31-16-165:~/bitcoin/src$ ./bitcoin-cli  -testnet getaddressesbyaccount ""
[
  "2MxoU6Sz8gyWfLCF2b8a8Wv56VT1MHdSB2x",
  "2NEquFrdTthcctUv3tUkeNU7FbbkgMT2812"
]

Then, i go to https://blockchain.info/search?search=2NEquFrdTthcctUv3tUkeNU7FbbkgMT2812%22

The webpage told me unrecognized search pattern.

Is the bitcoin core address not recognised ?

I go to https://blockexplorer.com/

The webpage told me "no matching records found".

Which address format should i use

I use bitcoin core version 0.16.0

Can i change my bitcoin.conf file, so that i can get bitcoins in testnet from mining?

Thank you for your reply. I am writing the code. It is possible that i can send the code to you. Please send a message to me with your email, i will send the code to you.

The transactions are sent out successfully by the code now.

[opening]
vic@ubuntu:~/Downloads/bitcoin$ ./src/bitcoin-cli -regtest decoderawtransaction 010000000108fad212da1a0f5f361346d76d35a19d3a1d11f80dab8d010ee0e0f48855190a00000 0006a47304402203d7de998eb2ba1fab32cd61acaa2662a77ec9d11c043ac59afe906acdca2db37 022058981084f1e85f9fcbb6916d33e2f94c83ea1ef1dd561c78ec6ddf3e385b9739012102b0fca dc4850e308645ecb8e9fc9d6cd7401c27de20b9bfd3b4bfb8f9d9e1281bffffffff0260d4ff2901 0000001976a914befa430b26b29cd72d55d3a7b9da70abac76f61c88ac801a06000000000017a91 45e01d5143c397a78abb4bd5ee3459615a99aa8a48700000000
{
  "txid": "46c3a867a197b0bef5fb79660de6bd1743bd24dcf9389bb02cac293b48dab970",
  "hash": "46c3a867a197b0bef5fb79660de6bd1743bd24dcf9389bb02cac293b48dab970",
  "version": 1,
  "size": 223,
  "vsize": 223,
  "locktime": 0,
  "vin": [
    {
      "txid": "0a195588f4e0e00e018dab0df8111d3a9da1356dd74613365f0f1ada12d2fa08",
      "vout": 0,
      "scriptSig": {
        "asm": "304402203d7de998eb2ba1fab32cd61acaa2662a77ec9d11c043ac59afe906acdca2db370220589 81084f1e85f9fcbb6916d33e2f94c83ea1ef1dd561c78ec6ddf3e385b9739[ALL] 02b0fcadc4850e308645ecb8e9fc9d6cd7401c27de20b9bfd3b4bfb8f9d9e1281b",
        "hex": "47304402203d7de998eb2ba1fab32cd61acaa2662a77ec9d11c043ac59afe906acdca2db3702205 8981084f1e85f9fcbb6916d33e2f94c83ea1ef1dd561c78ec6ddf3e385b9739012102b0fcadc485 0e308645ecb8e9fc9d6cd7401c27de20b9bfd3b4bfb8f9d9e1281b"
      },
      "sequence": 4294967295
    }
  ],
  "vout": [
    {
      "value": 49.99599200,
      "n": 0,
      "scriptPubKey": {
        "asm": "OP_DUP OP_HASH160 befa430b26b29cd72d55d3a7b9da70abac76f61c OP_EQUALVERIFY OP_CHECKSIG",
        "hex": "76a914befa430b26b29cd72d55d3a7b9da70abac76f61c88ac",
        "reqSigs": 1,
        "type": "pubkeyhash",
        "addresses": [
          "mxvkV17H5X8Kc6msvSwb6tfTnk2tqyahJq"
        ]
      }
    },
    {
      "value": 0.00400000,
      "n": 1,
      "scriptPubKey": {
        "asm": "OP_HASH160 5e01d5143c397a78abb4bd5ee3459615a99aa8a4 OP_EQUAL",
        "hex": "a9145e01d5143c397a78abb4bd5ee3459615a99aa8a487",
        "reqSigs": 1,
        "type": "scripthash",
        "addresses": [
          "2N1pHhdSyb6D8b6TAea26CWX6KbWfHkDxQ4"
        ]
      }
    }
  ]
}

[refund]
vic@ubuntu:~/Downloads/bitcoin$ ./src/bitcoin-cli -regtest decoderawtransaction 010000000170b9da483b29ac2cb09b38f9dc24bd4317bde60d6679fbf5beb097a167a8c34601000 000da0047304402205af0c4506b679c2d668246a5019f8cba6cbd42076cf5964d77f7230020e3b8 b002202da677710b2c328a55128375360ac5ca2aba7733cb174d63a2794fc50ee4b250014830450 221008b45af9b246713177b153833d7067b3266c2e67f4f1ccadd6664e3d04ac3140c022072a484 b83c97554c076035c1159f6f0a8d764a535021cd395033d6a0d720de110147522102b0fcadc4850 e308645ecb8e9fc9d6cd7401c27de20b9bfd3b4bfb8f9d9e1281b21030fa1d5fb74a8fa0383a024 d5e55671d2d3c45ed1fd8aea97a27a6a2e01926df852ae0000000001801a0600000000001976a91 4befa430b26b29cd72d55d3a7b9da70abac76f61c88ac54010000
{
  "txid": "e65826dae4ea499eb5e085e0d3e9b02fd3f9caa0be26115f019db2ea02a71d4d",
  "hash": "e65826dae4ea499eb5e085e0d3e9b02fd3f9caa0be26115f019db2ea02a71d4d",
  "version": 1,
  "size": 303,
  "vsize": 303,
  "locktime": 340,
  "vin": [
    {
      "txid": "46c3a867a197b0bef5fb79660de6bd1743bd24dcf9389bb02cac293b48dab970",
      "vout": 1,
      "scriptSig": {
        "asm": "0 304402205af0c4506b679c2d668246a5019f8cba6cbd42076cf5964d77f7230020e3b8b002202da 677710b2c328a55128375360ac5ca2aba7733cb174d63a2794fc50ee4b250[ALL] 30450221008b45af9b246713177b153833d7067b3266c2e67f4f1ccadd6664e3d04ac3140c02207 2a484b83c97554c076035c1159f6f0a8d764a535021cd395033d6a0d720de11[ALL] 522102b0fcadc4850e308645ecb8e9fc9d6cd7401c27de20b9bfd3b4bfb8f9d9e1281b21030fa1d 5fb74a8fa0383a024d5e55671d2d3c45ed1fd8aea97a27a6a2e01926df852ae",
        "hex": "0047304402205af0c4506b679c2d668246a5019f8cba6cbd42076cf5964d77f7230020e3b8b0022 02da677710b2c328a55128375360ac5ca2aba7733cb174d63a2794fc50ee4b25001483045022100 8b45af9b246713177b153833d7067b3266c2e67f4f1ccadd6664e3d04ac3140c022072a484b83c9 7554c076035c1159f6f0a8d764a535021cd395033d6a0d720de110147522102b0fcadc4850e3086 45ecb8e9fc9d6cd7401c27de20b9bfd3b4bfb8f9d9e1281b21030fa1d5fb74a8fa0383a024d5e55 671d2d3c45ed1fd8aea97a27a6a2e01926df852ae"
      },
      "sequence": 0
    }
  ],
  "vout": [
    {
      "value": 0.00400000,
      "n": 0,
      "scriptPubKey": {
        "asm": "OP_DUP OP_HASH160 befa430b26b29cd72d55d3a7b9da70abac76f61c OP_EQUALVERIFY OP_CHECKSIG",
        "hex": "76a914befa430b26b29cd72d55d3a7b9da70abac76f61c88ac",
        "reqSigs": 1,
        "type": "pubkeyhash",
        "addresses": [
          "mxvkV17H5X8Kc6msvSwb6tfTnk2tqyahJq"
        ]
      }
    }
  ]
}

[commitment]
vic@ubuntu:~/Downloads/bitcoin$ ./src/bitcoin-cli -regtest decoderawtransaction 010000000170b9da483b29ac2cb09b38f9dc24bd4317bde60d6679fbf5beb097a167a8c34601000 000db004830450221009e5d98cf5aaa6ea65bf9bab0b24031e1ea7f750f0aaf6040b497d42d96ce 671c02204f6888bae3603b88c4f1ad67a417c1da76007b4420394122f5420b784dc215100148304 50221008460f60e8187e2f429751e33c1201edab11a33d117c1b17e3517c1f7bd0bf20f02205934 911dd13919d9994090c38fc44b32550882aa38080c12977fbfe973d19f040147522102b0fcadc48 50e308645ecb8e9fc9d6cd7401c27de20b9bfd3b4bfb8f9d9e1281b21030fa1d5fb74a8fa0383a0 24d5e55671d2d3c45ed1fd8aea97a27a6a2e01926df852ae0000000002dc050000000000001976a 9143f8262c9c4fcc5285ff4d54ac5eb243180a2523588ac84110600000000001976a914befa430b 26b29cd72d55d3a7b9da70abac76f61c88ac00000000
{
  "txid": "14068565188fd3e7bea5cdfadc6377cf5db47f559e508a4e9926331e020967fd",
  "hash": "14068565188fd3e7bea5cdfadc6377cf5db47f559e508a4e9926331e020967fd",
  "version": 1,
  "size": 338,
  "vsize": 338,
  "locktime": 0,
  "vin": [
    {
      "txid": "46c3a867a197b0bef5fb79660de6bd1743bd24dcf9389bb02cac293b48dab970",
      "vout": 1,
      "scriptSig": {
        "asm": "0 30450221009e5d98cf5aaa6ea65bf9bab0b24031e1ea7f750f0aaf6040b497d42d96ce671c02204 f6888bae3603b88c4f1ad67a417c1da76007b4420394122f5420b784dc21510[ALL] 30450221008460f60e8187e2f429751e33c1201edab11a33d117c1b17e3517c1f7bd0bf20f02205 934911dd13919d9994090c38fc44b32550882aa38080c12977fbfe973d19f04[ALL] 522102b0fcadc4850e308645ecb8e9fc9d6cd7401c27de20b9bfd3b4bfb8f9d9e1281b21030fa1d 5fb74a8fa0383a024d5e55671d2d3c45ed1fd8aea97a27a6a2e01926df852ae",
        "hex": "004830450221009e5d98cf5aaa6ea65bf9bab0b24031e1ea7f750f0aaf6040b497d42d96ce671c0 2204f6888bae3603b88c4f1ad67a417c1da76007b4420394122f5420b784dc21510014830450221 008460f60e8187e2f429751e33c1201edab11a33d117c1b17e3517c1f7bd0bf20f02205934911dd 13919d9994090c38fc44b32550882aa38080c12977fbfe973d19f040147522102b0fcadc4850e30 8645ecb8e9fc9d6cd7401c27de20b9bfd3b4bfb8f9d9e1281b21030fa1d5fb74a8fa0383a024d5e 55671d2d3c45ed1fd8aea97a27a6a2e01926df852ae"
      },
      "sequence": 0
    }
  ],
  "vout": [
    {
      "value": 0.00001500,
      "n": 0,
      "scriptPubKey": {
        "asm": "OP_DUP OP_HASH160 3f8262c9c4fcc5285ff4d54ac5eb243180a25235 OP_EQUALVERIFY OP_CHECKSIG",
        "hex": "76a9143f8262c9c4fcc5285ff4d54ac5eb243180a2523588ac",
        "reqSigs": 1,
        "type": "pubkeyhash",
        "addresses": [
          "mmJm4WXW3u1mUj2rihPoDYp4GsPit6Ng8W"
        ]
      }
    },
    {
      "value": 0.00397700,
      "n": 1,
      "scriptPubKey": {
        "asm": "OP_DUP OP_HASH160 befa430b26b29cd72d55d3a7b9da70abac76f61c OP_EQUALVERIFY OP_CHECKSIG",
        "hex": "76a914befa430b26b29cd72d55d3a7b9da70abac76f61c88ac",
        "reqSigs": 1,
        "type": "pubkeyhash",
        "addresses": [
          "mxvkV17H5X8Kc6msvSwb6tfTnk2tqyahJq"
        ]
      }
    }
  ]
}

the complete raw transaction hex string can be seen below:
 
ubuntu:$ ./bitcoin-cli -regtest decoderawtransaction 01000000015b1544826bccad06ffa14902877fd367dd74289e8460bf9eb90da6315941462100000 000db00483045022100d8cc7539af4eb0e779434098ee5a5fb61d0de3947aafda0b5bc36b97c944 c50602201dfc82f276f8fc23ae3b8926a893c3a0abb9c42a75c8d1f274ab7a9b7c90c76d0148304 5022100d8cc7539af4eb0e779434098ee5a5fb61d0de3947aafda0b5bc36b97c944c50602201dfc 82f276f8fc23ae3b8926a893c3a0abb9c42a75c8d1f274ab7a9b7c90c76d0147522103d01115d54 8e7561b15c38f004d734633687cf4419620095bc5b0f47070afe85a2103d01115d548e7561b15c3 8f004d734633687cf4419620095bc5b0f47070afe85a52ae000000000260e31600000000001976a 914dd100be7d9aea5721158ebde6d6a1fd8fff93bb188ac60e31600000000001976a914dd100be7 d9aea5721158ebde6d6a1fd8fff93bb188ac00000000

Sending this raw transaction gives "bad-txns-in-belowout" error.

The funding transaction was created using bitcoin-cli generatetoaddress  command.

Yes, the address is on regtest.

When i want to send a raw transaction, i got the error of “bad-txns-in-belowout”.

Using decoderawtransaction, i got the txid of the only one vin, and the value of two vout are set at 0.015 BTC.
 
./bitcoin-cli -regtest decoderawtransaction "hexvalue"
{
  "txid": "35d2e765217d71db34fd0cd1cf52f419fc525069ac87ed9f413b194851c70849",
  "hash": "35d2e765217d71db34fd0cd1cf52f419fc525069ac87ed9f413b194851c70849",
  "version": 1,
  "size": 338,
  "vsize": 338,
  "locktime": 0,
  "vin": [
    {
      "txid": "2146415931a60db99ebf60849e2874dd67d37f870249a1ff06adcc6b8244155b",
      "vout": 0,
'''
    }
  "vout": [
    {
      "value": 0.01500000,
      "n": 0,
      "scriptPubKey": {
        "asm": "OP_DUP OP_HASH160 dd100be7d9aea5721158ebde6d6a1fd8fff93bb1 OP_EQUALVERIFY OP_CHECKSIG",
        "hex": "76a914dd100be7d9aea5721158ebde6d6a1fd8fff93bb188ac",
        "reqSigs": 1,
        "type": "pubkeyhash",
        "addresses": [
          "n1fprNxRhWrpkJ34A4cNsSZbHsnzhob2KL"
        ]
      }
    },
    {
      "value": 0.01500000,
      "n": 1,
...
    }
}

Using the command, i can see the amount and fee of vin.

./bitcoin-cli -regtest gettransaction 2146415931a60db99ebf60849e2874dd67d37f870249a1ff06adcc6b8244155b
{
  "amount": -0.08000000,
  "fee": -0.00100000,
  "confirmations": 0,
  "trusted": true,
  "txid": "2146415931a60db99ebf60849e2874dd67d37f870249a1ff06adcc6b8244155b",
...
}
   
Is there a command to check the output 0 value of txid 2146415931a60db99ebf60849e2874dd67d37f870249a1ff06adcc6b8244‌​155b ? It is the txid of vin.

So in "bitcoin-tx -create in=0fb9df5614be8b33be0434ce4062750d83f1b7ce05cc1296604f82eb9abf802b:0 ...."
The 0fb9df5614be8b33be0434ce4062750d83f1b7ce05cc1296604f82eb9abf802b is the txid.

Thank you.

We can use the command "bitcoin-tx -create --help"  to see the explanation of the options in the command.

I read the link about raw transaction format. It says raw transaction has version, tx_in count, Tx_in, TX_out count, Tx_out and lock time.

I can't relate this format to the hex value in the input part.

It is updated. Welcome to check it
https://embedded-design-vic.blogspot.com/

i figure it out.

Thank you. Now I use the bitcoin-tx binary.

bitcoin-tx -create in=0fb9df5614be8b33be0434ce4062750d83f1b7ce05cc1296604f82eb9abf802b:0 outscript=0.00159999:"DUP HASH160 0x14 0x6793a38f79b8cd51dbb6face6dc75a4af5c1bf29 EQUALVERIFY CHECKSIG"

and got the return value
02000000012b80bf9aeb824f609612cc05ceb7f1830d756240ce3404be338bbe1456dfb90f00000 00000ffffffff01ff700200000000001976a9146793a38f
79b8cd51dbb6face6dc75a4af5c1bf2988ac00000000

i understand the outscript format. 0.00159999 is the value to be spent. What about the in format ? what is 0fb9df56..... ? It is previous tx or scriptSig?

where are the bitcoin core files that handle P2SH transaction ?

I try to draw the table row and column line, but i don't know how to draw the line using the post reply formatter.

I found his book online, the scripting chapter is at
https://github.com/bitcoinbook/bitcoinbook/blob/second_edition/ch07.asciidoc

For P2SH, i understand it lets the sender funds a transaction using 20 byte hash. The script supplied to redeem must hash to the scriptHash.

scriptPubKey: OP_HASH160 <scriptHash> OP_EQUAL
scriptSig: 0 <sig1> ... <script> OP_m <pubKey1> ... OP_n OP_CHECKMULTISIG

For this example, the processing is:

The checking process:

Stack	Script	Description
Empty.	0 <sig1> <sig2> OP_2 <pubKey1> <pubKey2> <pubKey3> OP_3 OP_CHECKMULTISIG OP_HASH160 <scriptHash> OP_EQUAL	locking script combined with redeem script
0 <sig1> <sig2> OP_2 <pubKey1> <pubKey2> <pubKey3> OP_3	OP_CHECKMULTISIG OP_HASH160 <scriptHash> OP_EQUAL	Constants are added to the stack.
true	OP_HASH160 <scriptHash> OP_EQUAL	Signatures validated in the order of the keys in the script.

what happens after OP_CHECKMULTISIG, what value does OP_HASH160 hash to?

Thank you very much. finally understand it.

I read the link. I am still not clear. In
scriptPubKey: OP_DUP OP_HASH160 <pubKeyHash> OP_EQUALVERIFY OP_CHECKSIG
scriptSig: <sig> <pubKey>

The scriptSig contains the <sig> sender signature and <pubKey> sender public key, the scriptPubKey contains <pubKeyHash> which is the hash of receiver public key.

Then, how can the hash of sender <pubKey> matches with the receiver <pubKeyHash>  ?