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Hi Team,
I am using Azure app service, APIM, Azure functions etc. and due to some use case, I need to pass the request header field with 20kb size. However, as per the documentations, below are the default size as per web server.
I want to know the limit of 'HTTP Request header field size' for azure resources (e.g. azure app service, APIM, Azure functions etc.) for Windows as well as Linux operating system & how can we increase it?
Thanks in advance.
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@Jaydeep Suryawanshi out of curiosity, what is the use case here?
We have solution where we need to send some request header with bit big value ~30kb. Also, some of the APIs are behind APIM. So, just wanted to sure that we should not get 413 HTTP error due to the request header length limit.
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Hi Jaydeep Suryawanshi Thanks for your patience the limit of Request header field size for APIM is 64K and it can't be increased further.
Please let me know if you have any further queries.
Please ‘Upvote’ if it helped so that it can help others in the community looking for help on similar topics.
Hi thanks for the question
App Service/Functions
The request header length is controlled by the app service front ends (so irrespective of the backend hosting choice which could be container, windows, linux etc). this is a hard limit of 64KB (it cannot be changed)
This includes app service hosted functions using an http trigger.
API Management
I dont know about Azure API Management, I can ask and revert here.
Thank you @Ben Gimblett for the information. I will wait for the information around APIM.