HTTP

HTTP 102 Processing vs 503 Service Unavailable

HTTP 102 (Processing) is a 1xx Informational response, while 503 (Service Unavailable) is a 5xx Server Error response. 102 indicates that the server has received and is processing the request, but no response is available yet. Prevents the client from timing out. In contrast, 503 means that the server is temporarily unable to handle the request due to maintenance or overload. Should include a Retry-After header.

Description

The server has received and is processing the request, but no response is available yet. Prevents the client from timing out.

When You See It

During long-running WebDAV operations.

How to Fix

Wait for the final response. This is an interim status to prevent timeouts.

Description

The server is temporarily unable to handle the request due to maintenance or overload. Should include a Retry-After header.

When You See It

During maintenance windows, server overload, or when the application pool is exhausted.

How to Fix

Wait and retry. Check the Retry-After header. Scale up servers if it's a capacity issue.

Key Differences

1.

102 is a 1xx Informational response, while 503 is a 5xx Server Error response.

2.

HTTP 102: The server has received and is processing the request, but no response is available yet. Prevents the client from timing out.

3.

HTTP 503: The server is temporarily unable to handle the request due to maintenance or overload. Should include a Retry-After header.

4.

You encounter 102 when during long-running WebDAV operations.

5.

You encounter 503 when during maintenance windows, server overload, or when the application pool is exhausted.

When to Use Which

For 102 (Processing): Wait for the final response. This is an interim status to prevent timeouts. For 503 (Service Unavailable): Wait and retry. Check the Retry-After header. Scale up servers if it's a capacity issue.

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