11 days ago
My application has suddenly become inaccessible on major mobile networks in India (specifically Jio and Airtel), returning a DNS_PROBE_FINISHED_NXDOMAIN error.
Observations:
Office Network: The application loads perfectly. (Likely using global DNS servers).
Mobile/Home Network: The application fails to load with a DNS error.
Timeline: This issue appeared recently; the URL was working fine on all networks a few days ago.
Debugging: I have confirmed this is not a firewall issue on my end. It appears that the default
up.railway.appdomain is failing to resolve on specific ISPs in my region.
1 Replies
11 days ago
It looks like you’re running into DNS filtering issues from Indian ISPs (notably Jio and Airtel). This is not a Railway outage — several mobile providers in India have recently started blocking or failing to resolve dynamic subdomains like *.up.railway.app, similar to what happened to *.herokuapp.com, *.vercel.app, and other free hostnames.
Your app still loads correctly on corporate networks because they use global DNS resolvers (Google, Cloudflare), but mobile/home networks rely on the ISP’s DNS servers, which are applying stricter filtering.
The fix is to attach a custom domain to your Railway project.
Go to:
Project → Networking → Add Custom Domain
Then create a CNAME:
app.yourdomain.com → yourproject.up.railway.app
Once you access the app through a private domain, ISPs won’t filter it anymore and the problem disappears instantly.
(Optional temporary workaround: switching the device DNS to Cloudflare 1.1.1.1 or Google 8.8.8.8 will bypass the ISP filter.)
Let me know if you need help configuring the custom domain — it’s a common issue and easy to fix.
best kamkara