Solving: This site can't be reached

<section data-background="images/25-linux-site-cannot-be-reached/sleeping.jpg" data-state="frontpage">
<div class="atitle2">Accommodation Key Code at booking.com:</div><br>    
<div class="atitle" style="font-size:200% !important"><span class="db8orange">This site can’t be reached</span></div>
     <div class="atitle2"><br>
        <br><br><br><br>
        <span class="apage1">by Peter Martin / <a href="https://db8.nl" target="_blank">db8.nl</a></span>
        <br>
        <span class="apage1">slides: <a href="https://slides.db8.nl" target="_blank">https://slides.db8.nl</a></span>
        <style>.atitle{text-shadow: 2px 2px 2px #000;}
        .atitle2{text-shadow: 2px 2px 2px #000;}
        </style>
        <div style="margin: 0 auto;">
        <a href="https://db8.nl" title="Joomla Specialist db8 Nijmegen" target="_blank">
            <img height="50" style="border:0;background:transparent;margin-right:20px;
            box-shadow: 0 0 0 rgba(0, 0, 0, 0.15);" src="images/db8-logo.svg" alt="db8">
        </a>
    </div>
</div>

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<div class="title"><span class="db8orange">York, UK</span><br>summer holiday 2025</div>

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### My Family Summer Holiday 2025

- <span class="db8orange">England</span>: Harwich, Cambridge (Computer History Museum!), York
- <span class="db8orange">Scotland</span>: Glendevon, Edinburgh, Aberdeen
- <span class="db8orange">England</span>: Keshwick (Lake district), Nottingham, Harwich
- Some locations booked via <span class="db8orange">booking.com</span>

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### York:
> Hello Peter, Thank you for booking with us, we hope you are looking forward to your stay in York!<br>
<span class="db8orange">The self check in details will be sent to you via message within the 24 hours prior to your arrival.</span><br>
If you have any questions about your stay please dont hesitate to drop us a message.<br>
Speak soon,

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### York accommodation

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### Booking.com App does not work...

<span class="fragment db8orange">Other internet Mobile Apps work fine!</span>

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### Booking.com website does not work...

<span class="fragment db8orange">Other sites work fine!</span>

----

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### Printed itinerary + WhatsApp to the rescue

- I had a print out of every booking confirmation
- had phone number of host
- contacted host via whatsapp
- they responded within 10 minutes

---

<div class="title"><span class="db8orange">Diagnose</span><br>the issue</div>

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### Mobile App issue?

- Booking.com <span class="db8orange">fails to load</span> in **the mobile app**
- Error: `ERR_TIMED_OUT` or infinite loading on Google Chrome and Firefox
- No reports on https://allestoringen.nl/
- Affects <span class="db8orange">multiple devices</span> when using <span class="db8orange">hotspot</span> from a phone with Odido SIM

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### Network issue?

```ssh
ping 1.1.1.1
```

Network works ok!

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### DNS issue?

```ssh
ping booking.com
```

works ok! No DNS issue.

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### SSL/TLS issue?

```ssh
curl https://www.booking.com
```

works ok. No https:// issue

----

### Firewall issue?

```ssh
$ sudo ufw status
```

Status: inactive

so no firewall issue

----

### CLI browser?

```ssh
w3m https://www.booking.com
```

works, but does not support JavaScript,<br>needed for the site...

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### using <span class="db8orange">some local WiFi</span> network?

- <span class="db8orange">Mobile App</span> works
- <span class="db8orange">Website works</span> in Chrome and Firefox browser

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### Root Cause

- **Phone used roaming "3 UK"** as default network
- This network **broke HTTPS access** to Booking.com and/or its CDN
- Switching to another UK provider (e.g. **Vodafone**) manually **resolved the issue**

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### Network issues 3 UK < > Odido?

- **3 UK** routing or firewall issues
  - Broken access to Amazon CloudFront (used by Booking.com)
  - HTTPS filtering or misconfigured transparent proxy

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### <span class="db8orange">Solution</span>:
- On the phone:
    - Go to <span class="db8orange">Network and Internet Settings</span>
    - Go to <span class="db8orange">SIMs</span>
    - Disable <span class="db8orange">automatically select network</span>
    - <span class="db8orange">Choose</span> a different UK network <span class="db8orange">manually</span> (Vodafone or O2)

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### Conclusion

- Not a device issue
- Not an Odido ISP issue
- Not a DNS or browser issue
- It's a <span class="db8orange">roaming network problem</span> on <span class="db8orange">3 UK</span>
- Easily <span class="db8orange">fixed by switching mobile network</span>

---

<div class="title"><span class="db8orange">Bonus!</span></div>

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### Cashless Parking

<span style="font-size:80%" class="fragment">
EasyPark: EasyPark-app not yet available in UK, use RingGo-app.
<img height="400" style="border:0;background:transparent;margin-right:20px;
box-shadow: 0 0 0 rgba(0, 0, 0, 0.15);" src="images/25-linux-site-cannot-be-reached/ringgo-app.png" alt="Ringgo">
</span><br>
<span class="fragment">
Don't bother. You cannot add Dutch license plate, it does not recognize it and cannot find model car.
</span>

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### Customer Loyalty Cards

<span class="fragment">
Search images "[name] <span class="db8orange">discount card</span>" </span>

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### Laptop unused for 2.5 weeks

<span class="fragment" style="font-size: 80%">
<span class="db8orange">KERNEL PANIC!</span><br>
Please reboot your computer.<br>
VFS: Unable to mount root fs on unknown-block(0,0)
</span>
<span class="fragment">
<img height="350" style="border:0;background:transparent;margin-right:20px;float:left;
box-shadow: 0 0 0 rgba(0, 0, 0, 0.15);" src="images/25-linux-site-cannot-be-reached/kernel-panic.jpg" alt="Kernel Panic">
</span>
<span class="fragment">
<img height="100" style="border:0;background:transparent;margin-right:20px;float:right;
box-shadow: 0 0 0 rgba(0, 0, 0, 0.15);" src="images/25-linux-site-cannot-be-reached/reboot-older-image.jpg" alt="Kernel Panic">
</span>

---

<div class="title"><span class="db8orange">Questions?</span></div>

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## Photo Credits

<ul style="font-size:50%">
<li>https://unsplash.com/photos/person-in-gray-and-white-sweater-driving-car-hJlTr3t5fKY</li>
<li>Foto by Peter Martin</li>
<li>Foto by Google Street View</li>
<li>https://unsplash.com/photos/yellow-and-black-tissue-roll-egqR_zUd4NI</li>
<li>https://unsplash.com/photos/black-and-red-digital-device-g8Pr-LbVbjU</li>
<li>https://unsplash.com/photos/a-close-up-of-a-scrabble-type-word-on-a-table-7Hoil3HGH0o</li>
<li>https://ringgo.co.uk/</li>
<li>https://www.reddit.com/r/Donegal/comments/18ks77w/tesco_club_card_for_anybody_who_hasnt_got_one_and/</li>
<li>https://unsplash.com/photos/man-in-black-crew-neck-t-shirt-and-beige-pants-sitting-on-white-and-blue-stairs-XY0uyBhZWCA</li>
<li>Screen copy by Peter Martin</li>
</ul>

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