Hi everyone,
We are investigating an intermittent upload failure pattern and would
appreciate any community insights or official clarification.
When uploading files via the Box REST API using direct upload (non-chunked),
we have observed that some transfers are terminated mid-stream by the
server. The termination appears as TCP FIN followed by RST from
upload.box.com, with no HTTP response returned prior to disconnection.
This behavior occurs specifically on clients with lower network throughput,
which suggests the issue may be related to a time-based or throughput-based
threshold on the server side.
What we have ruled out:
- SSL inspection (not deployed in our environment)
- Intermediate proxy interference (packet analysis confirms server-initiated
disconnection from Box IP)
- HTTP-level rate limiting (no HTTP 429 received)
- Client-side timeout (the SDK does not initiate the disconnection)
Questions:
1. Has anyone encountered similar behavior where uploads from slower
clients are terminated mid-transfer without an HTTP response?
2. Is there any documented or community-known minimum throughput
requirement for Box upload sessions at the CDN/edge level?
3. For the Box team: Are there CDN-edge session policies (e.g., maximum
transfer duration, minimum data rate, or inactivity thresholds) that
apply to upload.box.com and are not covered in the public API
documentation?
Any pointers would be greatly appreciated. Thank you.