HTTP 101 Switching Protocols vs 413 Content Too Large
HTTP 101 (Switching Protocols) is a 1xx Informational response, while 413 (Content Too Large) is a 4xx Client Error response. 101 indicates that the server understands the Upgrade header field request and indicates which protocol it is switching to. In contrast, 413 means that the request payload exceeds the server's size limit.
Description
The server understands the Upgrade header field request and indicates which protocol it is switching to.
When You See It
When upgrading from HTTP/1.1 to WebSocket, or to HTTP/2.
How to Fix
This is normal behavior during protocol upgrades. Ensure your client supports the target protocol.
Description
The request payload exceeds the server's size limit.
When You See It
When uploading files that exceed the server's maximum upload size.
How to Fix
Reduce the payload size. Check server limits (Nginx: client_max_body_size, Apache: LimitRequestBody).
Key Differences
101 is a 1xx Informational response, while 413 is a 4xx Client Error response.
HTTP 101: The server understands the Upgrade header field request and indicates which protocol it is switching to.
HTTP 413: The request payload exceeds the server's size limit.
You encounter 101 when when upgrading from HTTP/1.1 to WebSocket, or to HTTP/2.
You encounter 413 when when uploading files that exceed the server's maximum upload size.
When to Use Which
For 101 (Switching Protocols): This is normal behavior during protocol upgrades. Ensure your client supports the target protocol. For 413 (Content Too Large): Reduce the payload size. Check server limits (Nginx: client_max_body_size, Apache: LimitRequestBody).