<p>Miners have been using the <a href="https://en.bitcoin.it/wiki/Protocol_documentation#block" rel="noreferrer">version field</a> of the blocks' headers as an "extra nonce" (<strong>*</strong>).</p>

<p>However, this version field has been used to signal readiness from miners to deploy a soft fork (update to new backward-compatible rules).</p>

<p>The version field being used to synchronize the update to new consensus rules is the reason you see the warning.</p>

<p>The version field value not being enforced by the consensus, and the development of <a href="https://blog.bitmex.com/graphical-illustration-of-a-bitcoin-block/" rel="noreferrer">new techniques that increase miners' revenue</a> is the reason they can "disgress" the protocol. </p>

<p>(<strong>*</strong>) In this specific case, it's known as version rolling and is likely part of using overt asicboost.</p>

<hr>

<p>EDIT - Some reference of discussions about how to deal with this in bitcoin-core :</p>

<ul>
<li><a href="https://github.com/bitcoin/bips/blob/master/bip-0320.mediawiki" rel="noreferrer">BIP320</a> <a href="https://github.com/bitcoin/bitcoin/pull/13972" rel="noreferrer">implementation</a></li>
<li>Discussions on <a href="https://github.com/bitcoin/bitcoin/issues/16343" rel="noreferrer">an issue</a></li>
<li><a href="https://github.com/bitcoin/bitcoin/pull/15471" rel="noreferrer">GUI warning removal</a></li>
</ul>

CC BY-SA 4.0
2020-06-09T14:57:21.600Z
2020-06-09T15:19:39.047Z
2020-06-09T15:19:39.047Z
Antoine Poinsot
<p>I've upgraded a node from the previous release. It's up and running but for some reasons I get this warning.
How can it be related to the upgrade?</p>

<pre><code>$ bitcoin-cli -testnet getblockchaininfo | jq
{
  "chain": "test",
  "blocks": 1764182,
  "headers": 1764182,
  "bestblockhash": "0000000000004a0e9cc1fbc2a21938feef1a26cd480483b3c498ae2ef16b46f8",
  "difficulty": 65536,
  "mediantime": 1591710673,
  "verificationprogress": 0.9999998260147338,
  "initialblockdownload": false,
  "chainwork": "00000000000000000000000000000000000000000000015bbad4a75d4239391e",
  "size_on_disk": 27411142847,
  "pruned": false,
  "softforks": {
    "bip34": {
      "type": "buried",
      "active": true,
      "height": 21111
    },
    "bip66": {
      "type": "buried",
      "active": true,
      "height": 330776
    },
    "bip65": {
      "type": "buried",
      "active": true,
      "height": 581885
    },
    "csv": {
      "type": "buried",
      "active": true,
      "height": 770112
    },
    "segwit": {
      "type": "buried",
      "active": true,
      "height": 834624
    }
  },
  "warnings": "Warning: unknown new rules activated (versionbit 28)"
}
</code></pre>

<bitcoin-core><block-header><asicboost>
"New rules activated" warning after upgrading to 0.20.0
Claudio
# "New rules activated" warning after upgrading to 0.20.0

(Asked by: username_0 on 2020-06-09)

I've upgraded a node from the previous release. It's up and running but for some reasons I get this warning.
How can it be related to the upgrade?

```
$ bitcoin-cli -testnet getblockchaininfo | jq
{
  "chain": "test",
  "blocks": 1764182,
  "headers": 1764182,
  "bestblockhash": "0000000000004a0e9cc1fbc2a21938feef1a26cd480483b3c498ae2ef16b46f8",
  "difficulty": 65536,
  "mediantime": 1591710673,
  "verificationprogress": 0.9999998260147338,
  "initialblockdownload": false,
  "chainwork": "00000000000000000000000000000000000000000000015bbad4a75d4239391e",
  "size_on_disk": 27411142847,
  "pruned": false,
  "softforks": {
    "bip34": {
      "type": "buried",
      "active": true,
      "height": 21111
    },
    "bip66": {
      "type": "buried",
      "active": true,
      "height": 330776
    },
    "bip65": {
      "type": "buried",
      "active": true,
      "height": 581885
    },
    "csv": {
      "type": "buried",
      "active": true,
      "height": 770112
    },
    "segwit": {
      "type": "buried",
      "active": true,
      "height": 834624
    }
  },
  "warnings": "Warning: unknown new rules activated (versionbit 28)"
}

```

**Tags:** bitcoin-core, block-header, asicboost


---

## 1 answers

### Answer by username_1 on 2020-06-09. Score: 5 | Accepted answer

Miners have been using the [version field](https://en.bitcoin.it/wiki/Protocol_documentation#block) of the blocks' headers as an "extra nonce" (**\***).

However, this version field has been used to signal readiness from miners to deploy a soft fork (update to new backward-compatible rules).

The version field being used to synchronize the update to new consensus rules is the reason you see the warning.

The version field value not being enforced by the consensus, and the development of [new techniques that increase miners' revenue](https://blog.bitmex.com/graphical-illustration-of-a-bitcoin-block/) is the reason they can "disgress" the protocol.

(**\***) In this specific case, it's known as version rolling and is likely part of using overt asicboost.

---

EDIT - Some reference of discussions about how to deal with this in bitcoin-core :

* [BIP320](https://github.com/bitcoin/bips/blob/master/bip-0320.mediawiki) [implementation](https://github.com/bitcoin/bitcoin/pull/13972)
* Discussions on [an issue](https://github.com/bitcoin/bitcoin/issues/16343)
* [GUI warning removal](https://github.com/bitcoin/bitcoin/pull/15471)


---

