2 months ago
Hello; the blog post for the accidental caching incident says "On Railway, CDN caching is opt-in. Domains without CDN enabled will always route requests directly to your application.". However, when inspecting browser requests to one of our services (app-server.arcol.io) which does not have the CDN enabled, those requests show some evidence of being routed through the CDN anyway - response headers include an X-Railway-Cdn-Edge header of the form fastly/cache-.... and an X-Served-By header with cache-.... I am pulling these values from a request with X-Railway-Request-Id of D8qpG_mJR0ODdFuZn6XIxQ
Can you clarify whether this is expected? If so, how do we reconcile that expectation with the claim that requests should go directly to the application? If not, are we potentially still at risk of accidental or erroneous caching of user requests?
3 Replies
Status changed to Awaiting Railway Response Railway • about 2 months ago
2 months ago
All edge traffic now routes through a Fastly layer as part of our networking infrastructure, so headers like X-Railway-Cdn-Edge and X-Served-By will appear on every request regardless of whether CDN is enabled for your domain. When CDN is not enabled, this layer acts strictly as a pass-through and does not cache any responses. The "CDN caching is opt-in" statement refers specifically to caching behavior, not the routing path. Your requests are not being cached.
Status changed to Awaiting User Response Railway • about 2 months ago
2 months ago
Got it - so the sentence "Domains without CDN enabled will always route requests directly to your application" should be understood to mean something more like "Domains without CDN enabled will still route requests to the CDN, but the CDN will act as a transparent pass-through"?
Status changed to Awaiting Railway Response Railway • about 2 months ago
2 months ago
Yeah, that's correct. It should say "Domains without CDN caching enabled will always route requests directly to your application, bypassing any sort of edge caching behavior".
Status changed to Awaiting User Response Railway • about 2 months ago
Status changed to Solved thomas-arcol • about 2 months ago