I am experiencing a selective network reachability issue affecting multiple custom domains hosted on Vercel.
Affected domains
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smartdex.ma -
www.smartdex.ma -
erp.gensalesmorocco.com
The corresponding *.vercel.app deployment URL is reachable from the same network, but the custom domains time out.
Network details
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Location: Casablanca, Morocco
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Fixed broadband ISP: Orange Morocco / MEDITELECOM
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ASN: AS36925
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Devices tested: macOS laptop and mobile phone
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Networks tested: home Wi-Fi, workplace Wi-Fi, and coffee-shop Wi-Fi
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Mobile 5G access works normally
TCP/443 results
These Vercel IP addresses consistently time out:
216.198.79.1:443216.198.79.65:44364.29.17.1:44364.29.17.65:443
These Vercel IP addresses are reachable from the same connection:
216.198.79.129:443216.198.79.193:44364.29.17.129:44364.29.17.193:443
For the reachable addresses:
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TCP connects successfully.
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TLS 1.3 completes.
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The correct certificate is returned.
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Vercel returns a valid HTTP/2 response.
DNS behavior
Normal DNS queries return the unreachable .1 and .65 addresses.
For example:
smartdex.ma → 64.29.17.1, 216.198.79.1
Google DNS returned:
smartdex.ma → 64.29.17.65, 216.198.79.65
The official Vercel debug script discovered the reachable .129 and .193 addresses, but those addresses are not returned during normal DNS resolution.
Traceroute
The last visible hops for the unreachable destinations are:
1 192.168.11.12 196.118.0.33 10.43.82.2054 10.43.82.2065 * * *...30 * * *
Important comparison
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Custom domains: unreachable
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smartdex-next.vercel.app: reachable -
Same devices over 5G: reachable
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General HTTPS connectivity, including Google: working