Hi,
from the DNS perspective both domains point to Google cloud, which reverses to projects.gitlab.io (see curl below). I don’t think that this is intended.
$ dig edstub.co.uk +short
35.185.44.232
$ dig photography.edstub.co.uk +short
35.185.44.232
You can learn about this with some more aggressive curl checks on the server header too.
$ curl -vvvvv -I -L photography.edstub.co.uk
* Trying 35.185.44.232...
* TCP_NODELAY set
* Connected to photography.edstub.co.uk (35.185.44.232) port 80 (#0)
> HEAD / HTTP/1.1
> Host: photography.edstub.co.uk
> User-Agent: curl/7.64.1
> Accept: */*
>
< HTTP/1.1 302 Found
HTTP/1.1 302 Found
< Content-Type: text/html; charset=utf-8
Content-Type: text/html; charset=utf-8
< Location: https://projects.gitlab.io/auth?domain=http://photography.edstub.co.uk&state=VP4wXN73zp78jNCGXvhLFQ==
Location: https://projects.gitlab.io/auth?domain=http://photography.edstub.co.uk&state=VP4wXN73zp78jNCGXvhLFQ==
< Set-Cookie: gitlab-pages=MTU3NjY4NTA1M3w3Y0lxdDNwN0x2ZEg5OVo1YUdacVUyRmljRExVS1Y0OU11aDF5VDllY21BWU55R2p1M0gxVmJhM0ZQR01taTNnYXNqcVlVSUp4UUd4MWhldTNUQW01RW9wWkR3S0FvbW5ka1lpMks3by1FdmJxcDVlMTBKT0Q4Q2lHeFl6UGxKNUVjQ1piTUQyS09XSGJ3XzU3SG5mTjBqcEVJTlhfd0Q3R3RfdF9RY0oyUWJPeHVrZ2VIdzMyX0VrZERHSC1NU258_20Zcw8nWJr4y-ujQNMUiqMdT-qY90zkuj-nkErDw_s=; Path=/; Expires=Wed, 18 Dec 2019 16:14:13 GMT; Max-Age=600; HttpOnly
Set-Cookie: gitlab-pages=MTU3NjY4NTA1M3w3Y0lxdDNwN0x2ZEg5OVo1YUdacVUyRmljRExVS1Y0OU11aDF5VDllY21BWU55R2p1M0gxVmJhM0ZQR01taTNnYXNqcVlVSUp4UUd4MWhldTNUQW01RW9wWkR3S0FvbW5ka1lpMks3by1FdmJxcDVlMTBKT0Q4Q2lHeFl6UGxKNUVjQ1piTUQyS09XSGJ3XzU3SG5mTjBqcEVJTlhfd0Q3R3RfdF9RY0oyUWJPeHVrZ2VIdzMyX0VrZERHSC1NU258_20Zcw8nWJr4y-ujQNMUiqMdT-qY90zkuj-nkErDw_s=; Path=/; Expires=Wed, 18 Dec 2019 16:14:13 GMT; Max-Age=600; HttpOnly
< Date: Wed, 18 Dec 2019 16:04:13 GMT
Date: Wed, 18 Dec 2019 16:04:13 GMT
<
* Connection #0 to host photography.edstub.co.uk left intact
* Issue another request to this URL: 'https://projects.gitlab.io/auth?domain=http://photography.edstub.co.uk&state=VP4wXN73zp78jNCGXvhLFQ=='
* Trying 35.185.44.232...
* TCP_NODELAY set
* Connected to projects.gitlab.io (35.185.44.232) port 443 (#1)
* ALPN, offering h2
* ALPN, offering http/1.1
* successfully set certificate verify locations:
* CAfile: /etc/ssl/cert.pem
CApath: none
* TLSv1.2 (OUT), TLS handshake, Client hello (1):
* TLSv1.2 (IN), TLS handshake, Server hello (2):
* TLSv1.2 (IN), TLS handshake, Certificate (11):
* TLSv1.2 (IN), TLS handshake, Server key exchange (12):
* TLSv1.2 (IN), TLS handshake, Server finished (14):
* TLSv1.2 (OUT), TLS handshake, Client key exchange (16):
* TLSv1.2 (OUT), TLS change cipher, Change cipher spec (1):
* TLSv1.2 (OUT), TLS handshake, Finished (20):
* TLSv1.2 (IN), TLS change cipher, Change cipher spec (1):
* TLSv1.2 (IN), TLS handshake, Finished (20):
* SSL connection using TLSv1.2 / ECDHE-RSA-CHACHA20-POLY1305
* ALPN, server accepted to use h2
* Server certificate:
* subject: OU=Domain Control Validated; CN=*.gitlab.io
* start date: Nov 19 01:00:05 2018 GMT
* expire date: Jan 18 07:59:59 2020 GMT
* subjectAltName: host "projects.gitlab.io" matched cert's "*.gitlab.io"
* issuer: C=BE; O=GlobalSign nv-sa; CN=AlphaSSL CA - SHA256 - G2
* SSL certificate verify ok.
* Using HTTP2, server supports multi-use
* Connection state changed (HTTP/2 confirmed)
* Copying HTTP/2 data in stream buffer to connection buffer after upgrade: len=0
* Using Stream ID: 1 (easy handle 0x7fd70b000000)
> HEAD /auth?domain=http://photography.edstub.co.uk&state=VP4wXN73zp78jNCGXvhLFQ== HTTP/2
> Host: projects.gitlab.io
> User-Agent: curl/7.64.1
> Accept: */*
>
* Connection state changed (MAX_CONCURRENT_STREAMS == 250)!
< HTTP/2 401
HTTP/2 401
< content-type: text/html; charset=utf-8
content-type: text/html; charset=utf-8
< x-content-type-options: nosniff
x-content-type-options: nosniff
< content-length: 2872
content-length: 2872
< date: Wed, 18 Dec 2019 16:04:13 GMT
date: Wed, 18 Dec 2019 16:04:13 GMT
<
* Connection #1 to host projects.gitlab.io left intact
* Closing connection 0
* Closing connection 1
That being said, either the DNS zone TTL is too high (3600s, 1h) and the provider changes are not in effect, or the provider did not configure DNS correctly with using a wildcard zone entry for any subdomain pointing to the GitLab pages IP address as default A record.
Cheers,
Michael