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This section describes how to handle client and server errors.
![[Note]](images/note.png) | Note |
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For information on specific error messages, see API Error Codes |
Do not retry client errors. Client errors indicate that Amazon SimpleDB found a problem with the client request and the application should address the issue before submitting the request again.
SOAP client errors are indicated by the client prefix and REST client errors are indicated by a 4xx HTTP response code.
For server errors, you should retry the requests.
SOAP server errors are indicated by the server prefix and REST server errors are indicated by a 5xx HTTP response code.
When retrying server errors, use exponential backoff. Exponential backoff is a strategy for reducing the load on the system and increasing the likelihood of repeated requests succeeding by incrementally decreasing the rate at which retries are executed. For example, client applications may wait up to 400 milliseconds before attempting the first retry, up to 1600 milliseconds before the second, up to 6400 milliseconds (6.4 seconds) before the third, and so on.
