an hour ago
Our production mobile app has lost traffic from mainland Chinese iOS users since approximately September 21, 2026, 01:00 UTC (10:00
KST).
The last successful request we identified was at 00:56:08 UTC. Other regions continue working.
Affected endpoint:
https://api-production-96da.up.railway.app
Resolves to: 69.46.46.45
Findings:
- Six mainland China probes, including China Unicom, China Mobile, Alibaba and Tencent networks, timed out establishing the TCP
connection.
- DNS resolution succeeds. The connection fails before TLS or HTTP, so there is no HTTP error or request ID.
- The same endpoint returns HTTP 200 from Seoul and Singapore.
- Our custom domain, https://api.mamalog.darak.studio, resolves to 69.46.46.43 and returns HTTPS 200 from three mainland China
probes.
- Both domains serve the same Railway service.
- No deployment occurred around the outage onset. The latest deployment was September 20 at 11:57:48 UTC.
Project ID: 037e9a52-cf62-4572-a7a0-8910308b2472
Service: api
Service ID: 99037d5c-eeeb-42c4-9014-6e59abaf83d2
Environment: production
Region: Southeast Asia
Deployment ID: 67d1f098-f0d3-431c-abca-1a54805cdc48
Measurements:
Failing China residential networks:
https://api.globalping.io/v1/measurements/2DoMnFWDZRZ1goBpL00021Aw1
Failing China cloud networks:
https://api.globalping.io/v1/measurements/2tD5eJ309WZj4P1Go00021Aw1
Working custom domain from China:
https://api.globalping.io/v1/measurements/2Fp1OTFia55cZuVfs00021Aw1
Working affected domain from Korea/Singapore:
https://api.globalping.io/v1/measurements/2h7hcXJzgMXSLaDrA00021Aw2
Could your networking team urgently investigate reachability to 69.46.46.45 from mainland China?
Can you restore connectivity or move the existing Railway-provided hostname to a reachable ingress IP without changing the hostname?
Installed mobile apps have this hostname hardcoded, so changing our custom domain alone will not restore access for existing users.
We have not determined whether this is filtering or a routing issue. Please investigate the network path and advise on immediate
mitigation.
1 Replies
an hour ago
This thread has been opened as a bounty so the community can help solve it.
Status changed to Open Railway • about 1 hour ago
an hour ago
If it's a regional block on railway generated domains caused by some ISPs in mainland china, your only option would be to use only the custom domain, since you verified there is no issue with it. Proxying the domain via cloudflare is also an option if you face similar issues with it. Alternatively, users can use a VPN to access the mobile app as a workaround in the meantime, as this isn't something Railway can resolve on their end.