# Fwd: Backend handling of Expect: 100-Continue header

**URL:** <https://www.ruby-forum.com/t/fwd-backend-handling-of-expect-100-continue-header/209596>\
**Category:** NGINX\
**Created:** [July 18, 2011, 3:49pm UTC](https://www.ruby-forum.com/t/fwd-backend-handling-of-expect-100-continue-header/209596 "2011-07-18T15:49:44Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![dubstep](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/cdc98d/32.png) [@dubstep](https://www.ruby-forum.com/u/dubstep)\
**Post date:** [July 18, 2011, 3:49pm UTC](https://www.ruby-forum.com/t/fwd-backend-handling-of-expect-100-continue-header/209596/1 "2011-07-18T15:49:44Z")

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Hi guys,

I am forwarding questions from my friend (it seems that he has some  
problems with posting to this group). Hope it’s OK for you.

Cheers,  
Kamil

---------- Forwarded message ----------  
From: Łukasz Osipiuk [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)  
Date: Mon, Jul 18, 2011 at 3:46 PM  
Subject: Fwd: Backend handling of Expect: 100-Continue header  
To: Kamil G. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)

---------- Forwarded message ----------  
From: Łukasz Osipiuk [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)  
Date: Mon, Jul 18, 2011 at 15:25  
Subject: Backend handling of Expect: 100-Continue header  
To: removed\_email\_address@domain.invalid

Hi!

I searched through archives and I see that topic appeared on the list  
in the past but I did not find  
any concrete answers.

We use nginx to proxy large PUT (100M+) requests to backend servers.  
When issuing an request clients sets “Expect: 100-Continue” header.

We noticed that nginx does not forward request to backend server until  
it consumes it completely.  
That is not what we want.

1. We need to disable automatic 100-Continue handling in nginx.  
Instead we need nginx to forward headers to backend server and let it  
determine if 100 Continue or final error code should be returned to  
client.
2. We need to disable request body buffering as we have upload request  
resuming implemented on the backend tier.

Are above achievable in current nginx version (maybe with some 3rd  
party modules)? AFAIK mogilefs module proxies uploaded file directly  
to backend servers withouth buffering.

Regards, Łukasz Osipiuk

–  
Łukasz Osipiuk  
[mailto:removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)

## –

Łukasz Osipiuk  
[mailto:removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)

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<div class="post-metadata">

**Author:** ![grymuz](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/779978/32.png) [@grymuz](https://www.ruby-forum.com/u/grymuz)\
**Post date:** [July 18, 2011, 5:17pm UTC](https://www.ruby-forum.com/t/fwd-backend-handling-of-expect-100-continue-header/209596/2 "2011-07-18T17:17:49Z")

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On Mon, Jul 18, 2011 at 03:48:51PM +0200, Kamil G. wrote:

> Hi guys,
> 
> I am forwarding questions from my friend (it seems that he has some  
> problems with posting to this group). Hope it’s OK for you.

He should subscribe to the list to eb able to write here.  
Currently his message was bounced.

> ---------- Forwarded message ----------  
> any concrete answers.  
> determine if 100 Continue or final error code should be returned to  
> client.  
> 2. We need to disable request body buffering as we have upload request  
> resuming implemented on the backend tier.
> 
> Are above achievable in current nginx version (maybe with some 3rd  
> party modules)? AFAIK mogilefs module proxies uploaded file directly  
> to backend servers withouth buffering.

Currently nginx does not support this, because it has been designed  
as accelerator to minimize backend interaction with a client.

–  
Igor S.