'Bad Request, Your browser sent a request that this server could not understand

There are two application servers and a switch. When i access application by using application server ip it works fine. However if i use switch ip in my url Bad request error throws up only for firefox and chrome for a few links only.

request

Solution 1:^[1]

Here is a detailed explanation & solution for this problem from ibm.

Problem(Abstract)

Request to HTTP Server fails with Response code 400.

Symptom

Response from the browser could be shown like this:

Bad Request Your browser sent a request that this server could not understand. Size of a request header field exceeds server limit.

HTTP Server Error.log shows the following message: "request failed: error reading the headers"

Cause

This is normally caused by having a very large Cookie, so a request header field exceeded the limit set for Web Server.

Diagnosing the problem

To assist with diagnose of the problem you can add the following to the LogFormat directive in the httpd.conf: error-note: %{error-notes}n

Resolving the problem

For server side: Increase the value for the directive LimitRequestFieldSize in the httpd.conf: LimitRequestFieldSize 12288 or 16384 For How to set the LimitRequestFieldSize, check Increase the value of LimitRequestFieldSize in Apache

For client side: Clear the cache of your web browser should be fine.

Solution 2:^[2]

If you use Apache httpd web server in version above 2.2.15-60, then it could be also because of underscore _ in hostname.

https://ma.ttias.be/apache-httpd-2-2-15-60-underscores-hostnames-now-blocked/

Solution 3:^[3]

I just deleted my stored cookies, site data, and cache from my browser... It worked. I'm using firefox...

Solution 4:^[4]

Make sure you url encode all of the query params in your url.

In my case there was a space ' ' in my url, and I was making an API call using curl, and my api server was giving this error.

Means the following url http://somedomain.com?key=some value with space

should be http://somedomain.com/?key=some%20value%20with%20space

Solution 5:^[5]

I was testing my application with special characters & was observing the same error. After some research, turns out the % symbol was the cause. I had to modify it to the encoded representation %25. Its all fine now, thanks to the below post

https://superuser.com/questions/759959/why-does-the-percent-sign-in-a-url-cause-an-http-400-bad-request-error

Solution 6:^[6]

I'm a bit late to the party, but bumped in to this issue whilst working with the openidc auth module.

I ended up noticing that cookies were not being cleared properly, and I had at least 10 mod_auth_openidc_state_... cookies, all of which would be sent by my browser whenever I made a request.

If this sounds familiar to you, double check your cookies!

Solution 7:^[7]

in my case:

in header

Content-Typespacespace

Content-Typetab

with two space or tab

when i remove it then it worked.

Solution 8:^[8]

In my case is a cookie-related issue, I had many cookies with value extremely big, and that was causing the problem.

You can replicate this issue here on stackoverflow.com, just open the console and type this:

[ ...Array(5) ].forEach((i, idx) => {
    document.cookie = `stackoverflow_cookie${idx}=${'a'.repeat(4000)}`;
});

What is that?

I am creating 5 cookies with a string of length or value of 4000 bytes; then reload the page and you will see the same issue.

I tried it on google.com and you'll get the error but they automatically clear the cookies for you, which is a nice fallback to start fresh.

Solution 9:^[9]

in my magento2 website ,show exactly the same error when click a product,

my solution is to go to edit the value of Search Engine Optimization - URL Key of this product,

make sure that there are only alphabet,number and - in URL Key, such as 100-washed-cotton-duvet-cover-set, deleting all other special characters ,such as % .

Solution 10:^[10]

I got Bad Request, Your browser sent a request that this server could not understand when I tried to download a file to the target machine using curl.
I solved it by instead using scp to copy the file from the source machine to the target machine.

Solution 11:^[11]

If you are getting this error on the WordPress website, check the below solution.

Corrupted Browser Cache & Cookies: Delete your Cookies and clear your cache
Restart your server

Solution 12:^[12]

For GET Request make sure that passing parameters are url encoded. if you are using php you can use urlencode function

Solution 13:^[13]

If you have this same problem and none of the other solutions worked, please check again the url.

In my case it was a space in the end, when it was added to the Cronjob, someone also copied a blank space by accident.

Solution 14:^[14]

check your data types are correct or not.

for ex: if you send the file, you need to consider to send the full object of the file

Solution 15:^[15]

THIS IS CAUSED BY TOO MANY COOKIES!

To SOLVE - Chrome: go into 'developer mode' -> ctrl + shift + i

On top you will see console, network and LITTLE BUTTON THAT LOOKS LIKE ARROWS >>> click on that for APPLICATION

On Left, under STORAGE, find COOKIES.

There will be little DOWN ARROW indicating a drop down, click on this.

now you will see the website something like: www.investing.com

RIGHT CLICK IT and select Clear

Reload.

Works!

Alternatively, clear cookies and cache in a traditional way, and it will work too.

Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution	Source
Solution 1	HoldOffHunger
Solution 2	BobÃk
Solution 3	Allegue
Solution 4	Mubashar Abbas
Solution 5	akimran82
Solution 6	Ang D
Solution 7	saber tabatabaee yazdi
Solution 8
Solution 9	bestshop24h
Solution 10	Henke
Solution 11	WorldWin Coder Pvt. Ltd
Solution 12	Thanura Jayasekara
Solution 13	tibelchior
Solution 14	janadari ekanayaka
Solution 15	fruitloaf

'Bad Request, Your browser sent a request that this server could not understand

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