<p>There's no reason why you need to change them if you're not concerned about running Bitcoin and an altcoin on the same device/IP address.</p>

CC BY-SA 3.0
2017-05-06T20:31:06.947Z
2017-05-06T20:31:06.947Z
Nick ODell
<p>The RPC port is the port used for tools such as <code>bitcoin-cli</code> to connect to the node and execute administrative commands (this is why it's bound by default to <code>localhost</code> / <code>127.0.0.1</code>).</p>

<p>The reason it should be changed is so that it doesn't create conflicts if you wanted to run your altcoin on the same system as a bitcoin node, since only one can use a given port.</p>

CC BY-SA 3.0
2017-05-06T23:08:08.320Z
2017-05-06T23:08:08.320Z
Darth Android
<p>In <a href="https://bitcointalk.org/index.php?topic=372545.0" rel="nofollow noreferrer">this outdated but seemingly comprehensive guide to creating an altcoin fork of bitcoin</a> they make special mention of the need to change the rpc port.</p>
<p>Although in the intervening time the file names have changed the variables remain so I think this advice is still valid.</p>
<p>What is the purpose of these ports? What information do they transmit? Why are they there and why must we change them when creating a new network?</p>
<hr />
<h1>Step 4- Ports(required)</h1>
<pre><code>a) bitcoinrpc.cpp 
    -change RPC port.

    Code:
    ip::tcp::endpoint endpoint(bindAddress, GetArg(&quot;-rpcport&quot;, 55883));

    Code:
    if (!d.connect(GetArg(&quot;-rpcconnect&quot;, &quot;127.0.0.1&quot;), GetArg(&quot;-rpcport&quot;, &quot;55883&quot;)))

b) init.cpp
   -change RPC port

    Code:
    -rpcport= &quot; + _(&quot;Listen for JSON-RPC connections on  (default: 55883)&quot;) + &quot;\n&quot; +

    -change Testnet and Common port(P2P).

    Code:
    -port= &quot; + _(&quot;Listen for connections on  (default: 55884 or testnet: 45884)&quot;) + &quot;\n&quot; +

c) protocol.h

  -Testnet and P2P port again.

    Code:
    return testnet ? 45883 : 55884;
</code></pre>

<json-rpc>
what is the significance of the rpc port and it's relation to the functionality of bitcoin
smatthewenglish
# what is the significance of the rpc port and it's relation to the functionality of bitcoin

(Asked by: username_0 on 2017-05-06)

In [this outdated but seemingly comprehensive guide to creating an altcoin fork of bitcoin](https://bitcointalk.org/index.php?topic=372545.0) they make special mention of the need to change the rpc port.

Although in the intervening time the file names have changed the variables remain so I think this advice is still valid.

What is the purpose of these ports? What information do they transmit? Why are they there and why must we change them when creating a new network?

---

# Step 4- Ports(required)

```
a) bitcoinrpc.cpp 
    -change RPC port.

    Code:
    ip::tcp::endpoint endpoint(bindAddress, GetArg("-rpcport", 55883));

    Code:
    if (!d.connect(GetArg("-rpcconnect", "127.0.0.1"), GetArg("-rpcport", "55883")))

b) init.cpp
   -change RPC port

    Code:
    -rpcport= " + _("Listen for JSON-RPC connections on  (default: 55883)") + "\n" +

    -change Testnet and Common port(P2P).

    Code:
    -port= " + _("Listen for connections on  (default: 55884 or testnet: 45884)") + "\n" +

c) protocol.h

  -Testnet and P2P port again.

    Code:
    return testnet ? 45883 : 55884;

```

**Tags:** json-rpc


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## 2 answers

### Answer by username_1 on 2017-05-06. Score: 2 | Accepted answer

There's no reason why you need to change them if you're not concerned about running Bitcoin and an altcoin on the same device/IP address.


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### Answer by username_2 on 2017-05-06. Score: 2

The RPC port is the port used for tools such as `bitcoin-cli` to connect to the node and execute administrative commands (this is why it's bound by default to `localhost` / `127.0.0.1`).

The reason it should be changed is so that it doesn't create conflicts if you wanted to run your altcoin on the same system as a bitcoin node, since only one can use a given port.


---

