SOLVED Error after installing apache module mod_http2

Anran

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Hi, I'm having issues using mod_http2 on Apache on our server. We are getting Failed to load resource: the server responded with a status of 431 () shown in the console of Chrome. The website is blank when the module is installed. We are also using Joomla. I uninstalled it and it returned back to normal. Is there some configuration needed in order to get it to work properly or a solution to fix the issue?
 

morrow95

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Oct 8, 2006
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For what its worth I also have been waiting on this module and just installed about a half hour ago. No problems at all and works fine. As pointed out above it sounds like a Joomla issue. Have you tried browsing a simple 'test page' on the server and using something like Chrome dev tools to view the protocol used? I'm just saying it might be worth trying something 'outside' of Joomla which would narrow down where the problem is coming from.
 
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Anran

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I tried a test page and got the same 431 error. So it must be on the server side somewhere. I'm not sure if Apache needs to configured in a way to be able to get it to work, since I don't know enough about configuring the module.
 

Anran

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I checked the Apache error log and see nothing out of the ordinary.
[Thu Jul 13 18:56:59.219585 2017] [http2:info] [pid 25523:tid 140232036194272] AH03090: mod_http2 (v1.8.3, feats=CHPRIO+SHA256+INVHD, nghttp2 1.20.0), initializing...
[Thu Jul 13 18:56:59.224916 2017] [mpm_event:notice] [pid 25523:tid 140232036194272] AH00489: Apache/2.4.25 (cPanel) OpenSSL/1.0.2k mod_bwlimited/1.4 configured -- resuming normal operations
[Thu Jul 13 18:56:59.224971 2017] [core:notice] [pid 25523:tid 140232036194272] AH00094: Command line: '/usr/sbin/httpd'
 

Anran

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So error code 431 is Request Header Fields Too Large and I don't know how to fix that with apache. The one fix I saw to increase the LimitRequestFieldSize did not work.
 

cPanelMichael

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So error code 431 is Request Header Fields Too Large and I don't know how to fix that with apache. The one fix I saw to increase the LimitRequestFieldSize did not work.
Have you tried clearing your browser cache in Chrome to see if the issue persists? Also, can you reproduce the issue from multiple web browsers?

Thank you.
 

Anran

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So it looks like Chrome is the only browser having this issue that I have the capability of testing. I even cleared the browser cache. I've tested on both Firefox and Safari and both of those aren't having issues. The Chrome version I have is 59.0.3071.115. I can't have Chrome having this issue, since there are customers and others visiting site using Chrome.
 

cPanelMichael

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So it looks like Chrome is the only browser having this issue that I have the capability of testing. I even cleared the browser cache. I've tested on both Firefox and Safari and both of those aren't having issues. The Chrome version I have is 59.0.3071.115. I can't have Chrome having this issue, since there are customers and others visiting site using Chrome.
Could you verify if Mod_Ruid2 is installed on your server, and if so, if the "EXPERIMENTAL: Jail Apache Virtual Hosts" option is enabled in "WHM >> Tweak Settings"? Also, are you using any antivirus applications such as NOD32 on the computer you are using to reproduce the issue?

While not necessarily related, we also have another thread open regarding Chrome and SSL access attempts from Windows machines:

https + chrome + OS problem

Could you review that thread and confirm your issue doesn't stem from the referenced case?

Thank you.
 

Anran

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Don't have mod_ruid installed and don't have the same issue as the other thread, but after looking extensively into this I think I found the solution. The browser used the cached cookie that was causing header error because it was too long, exceeding the limit allowed, and the mod_http2 module didn't seem to like it and completely clearing out the cookies fixed the issue on my end. I'm also not Windows, but on Mac OSX and maybe it was an issue with OSX version of the browser that would not update the cookies after a while. While this seems to have been fixed for me, others may have the issue using the same browser and unless they know to clear their cookies they may see what I saw before.