HI David
I have been working with Cloudflare as to why I am getting 520 error when editing posts in WordPress.
They are saying the plugin is causing large response headers which exceeds the 8kb limit CloudFlare allows.
Do you know why the plugin is creating large response headers?
Hello
The error message is showing upstream sent too big header while reading response header from upstream.
{
“_index”: “nginx-2016.07.28”,
“_type”: “nginx”,
“_id”: “AVYwIPi97pP_CcHnwOhm”,
“_score”: null,
“_source”: {
“id”: “2c962c0e8d9351eb”,
“timestamp”: “2016-07-28T06:11:17Z”,
“count”: 1,
“server”: “47m18”,
“flserver”: “47m18”,
“cacheserver”: “47c18”,
“severity”: “error”,
“pid”: “5900”,
“connectionId”: “13759077”,
“message”: “upstream sent too big header while reading response header from upstream”,
“client”: “xxx.xxx.xxx.xx”,
“request”: “GET /wp-admin/post.php?post=146668&action=edit HTTP/1.1”,
upstream”: “https://xxx.xxx.xxx.xxx/wp-admin/post.php?post=146668&action=edit,
“host”: “www.xxx.com”,
“location”: {
“colo”: “xxx”,
“coloId”: 47,
“coloGeo”: [
144.9631,
-37.8136
]
}
},
As shown in the above the upstream xxx.xxx.xxx.xx is sending too big a response header to CF server. Your web server is returning response headers exceeding CloudFlare’s header size limit (over 8kb). We are unable to change the response size limit.
