Balance is 0 after send transaction in testnet v0.19 and blocksonly flag enabled #17662

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I tried to send 0.00469484 BTC from 0.02 BTC total in testnet3. The daemon reports a txid but this one is not visible in any explorer and the transaction is not processing it at all. Furthermore the balance is set to 0.00000000 (getbalance "*" 0). I can query the transaction via listtransactions. It is a transaction from and to the same wallet. Also maybe related, in regtest mode some invisible fee is reduced from total wallet balance but not logged in any receive-send info. The amount is just missing.

<!--- What behavior did you expect? -->

Just send a test transaction

<!--- What was the actual behavior (provide screenshots if the issue is GUI-related)? -->

To reproduce

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System information

<!-- What version of Bitcoin Core are you using, where did you get it (website, self-compiled, etc)? -->

Bitcoin Core version v0.19.0.1 (release build) -blocksonly=1 -prune=1024

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Linux 4.15 (Ubuntu 18.04.1 LTS)

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<!--- This is normally the contents of a `debug.log` or `config.log` file. Raw text or a link to a pastebin type site are preferred. -->

There is nothing special logged:

2019-12-03T20:54:13Z [test] CommitTransaction:
CTransaction(hash=896cc84018, ver=2, vin.size=2, vout.size=2, nLockTime=1611085)
    CTxIn(COutPoint(21866e5057, 1), scriptSig=160014a5a09ce3f5f5d78d39, nSequence=4294967294)
    CTxIn(COutPoint(5a847af857, 0), scriptSig=160014a5a09ce3f5f5d78d39, nSequence=4294967294)
    CScriptWitness(304402207f290913ac2c796278b9ae2271f17c39e9039bbbfe6e37e6a3d9b97fd19d7928022004e46bceec87b3195ca0fe1477366ef21c9f9a11ffd7acec039a3dea8cf2839501, 02baab1863533372a82ced2b84009217fd81e83d3325d44e865970f3ffe9c7a162)
    CScriptWitness(304402206ba62fc2a8a37c59e7474f318021fd09c67e6b6b38aaf7ac10ec60125c04555c02204608cd5764f1c38f814b55f8e5629f0a69a2f07ac094505a1249d0524fa3ec0b01, 02baab1863533372a82ced2b84009217fd81e83d3325d44e865970f3ffe9c7a162)
    CTxOut(nValue=0.00469484, scriptPubKey=a914da26d8b5010fb615fe442b678c)
    CTxOut(nValue=0.01530260, scriptPubKey=a914fafbd45c56f6a2a593b115b0fa)

2019-12-03T20:54:13Z [test] AddToWallet 896cc8401843a2f7d0682a43faa180a5b2f722db96039a9d30b2158e3b7e97ea  new

{
    "address": "2ND8hqCu4r4Raj6paNk3FThSb9SZx8bad57",
    "category": "receive",
    "amount": 0.00469484,
    "label": "",
    "vout": 0,
    "confirmations": 0,
    "trusted": false,
    "txid": "896cc8401843a2f7d0682a43faa180a5b2f722db96039a9d30b2158e3b7e97ea",
    "walletconflicts": [
    ],
    "time": 1575406453,
    "timereceived": 1575406453,
    "bip125-replaceable": "unknown"
  },
  {
    "address": "2ND8hqCu4r4Raj6paNk3FThSb9SZx8bad57",
    "category": "send",
    "amount": -0.00469484,
    "label": "",
    "vout": 0,
    "fee": -0.00000256,
    "confirmations": 0,
    "trusted": false,
    "txid": "896cc8401843a2f7d0682a43faa180a5b2f722db96039a9d30b2158e3b7e97ea",
    "walletconflicts": [
    ],
    "time": 1575406453,
    "timereceived": 1575406453,
    "bip125-replaceable": "unknown",
    "abandoned": false
  }

Does maybe the peers do not accept my transaction? All peers have a lower version:

    "subver": "/Satoshi:0.18.0/",
    "subver": "/Satoshi:0.18.1/",
    "subver": "/Satoshi:0.16.0/",
    "subver": "/Satoshi:0.15.2/",
    "subver": "/Satoshi:0.17.0/",
    "subver": "/Satoshi:0.17.0/",
    "subver": "/Satoshi:0.18.0/",
    "subver": "/Satoshi:0.13.2/",
    "subver": "/Satoshi:0.14.2/",

@laanwj if you think that is not a bug that the core wipes my remaining balance and do not send the transaction could you please give me a hint whats going wrong here? thx

I have removed the -blocksonly flag and now my transaction is visible to the network (but was not before not even after some hours)

due to miners messing around with it all the time, testnet is unreliable, there's work on "signet" that would provide for more reliable testing by generating blocks more predictably

-blocksonly is not a good combination with the wallet, it means transactions will only become visible after they end up in a block this includes the change part to yourself, which explains why the balance is temporarily 0

@laanwj Thank you for your response

For public: I assume the transaction is silently rejected by the testnet because the core is unable to estimate the fee with -blocksonly (and tries to send with fee: 0?). In mainnet you will get an error about that. Conclusion: do not test with -blocksonly enabled in testmode.

-blocksonly interacts with -walletbroadcast. See also issue #17294 (comment)