**Tip:** The script provided in [$GIT_REPO/misc/netconf.sh](https://github.com/{{ site.github_username }}/open5gs/blob/main/misc/netconf.sh) makes it easy to configure the TUN device as follows:
**Note:** This should require *sudo* due to access `/dev/tun0`.
{: .notice--danger}
```bash
$ sudo ./build/tests/attach/attach ## EPC Only
$ sudo ./build/tests/registration/registration ## 5G Core Only
```
Run all test programs as below.
**Note:** This should require *sudo* due to access `/dev/tun0`.
{: .notice--danger}
```bash
$ cd build
$ sudo meson test -v
```
**Tip:** You can also check the result of `ninja -C build test` with a tool that captures packets. If you are running `wireshark`, select the `loopback` interface and set FILTER to `s1ap || gtpv2 || pfcp || diameter || gtp || ngap || http2.data.data || http2.headers`. You can see the virtually created packets. [testattach.pcapng]({{ site.url }}{{ site.baseurl }}/assets/pcapng/testattach.pcapng)/[testregistration.pcapng]({{ site.url }}{{ site.baseurl }}/assets/pcapng/testregistration.pcapng)
{: .notice--info}
You need to perform the **installation process**.
```bash
$ cd build
$ ninja install
$ cd ../
```
### Building WebUI of Open5GS
---
[Node.js](https://nodejs.org/) is required to build WebUI of Open5GS
```bash
$ brew install node
```
Install the dependencies to run WebUI
```bash
$ cd webui
$ npm install
```
The WebUI runs as an [npm](https://www.npmjs.com/) script.