# Change MTU Value

## Windows

We will perform the shift through the utility **CMD**.

You must first open a command prompt as administrator. Then use the appropriate command to view all existing network interfaces and values **MTU**.

```
netsh interface ipv4 show subinterfaces
```

<figure><img src="/files/AKrfAOVC57UHVWDKsrqe" alt=""><figcaption></figcaption></figure>

That’s pretty much the conclusion.

{% hint style="info" %}
Where **1500** (default) is the **MTU** value.\
**Ethernet** — standard interface name.
{% endhint %}

Next, change the **MTU** value with a special command:

```
netsh interface ipv4 set subinterface "Ethernet" mtu=1400 store=persistent
```

{% hint style="info" %}
Where **Ethernet** is the name of the network interface.&#x20;

**1400** - New MTU value set.
{% endhint %}

Get the result.

<figure><img src="/files/3wPH4wJixxNk1clCSwP0" alt=""><figcaption></figcaption></figure>

## Debian / Ubuntu

Enter command to edit configuration of network interfaces, will use **Nano**:

```
nano /etc/network/interfaces
```

Then add at the end of the network interface `mtu 1400`

<figure><img src="/files/HykeglfIZs03ziCUhhnE" alt=""><figcaption></figcaption></figure>

Press **Ctrl + X,** then **Y** to save the changes.

Enter the command to restart the network service:

```
systemctl restart networking
```


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