nginx net::ERR_SPDY_PROTOCOL_ERROR 200

Question

I'm getting this on some resources and it's preventing us from editing pages on the back end. I found the error in console in firefox:

Comments

I talked to someone who helped me further. We explored the nginx log and found some issues:

2019/02/17 00:38:05 [alert] 2459#2459: *46471 pread() read only 8553 of 8563 from "/var/www/domain.com/htdocs/wp-content/uploads/bb-plugin/cache/18-layout-preview.css" while sending response to client, client: 172.58.22.150, server: domain.com, request: "GET /wp-content/uploads/bb-plugin/cache/18-layout-preview.css?ver=4d453a398eb115bac296bd8be6f5cfb9 HTTP/2.0", host: "domain.com", referrer: "https://domain.com/?fl_builder"

We searched for "search pread() read only xxxx of yyyy" and this led us to look at the nginx config file. My friend, who is an nginx expert and runs a hosting company, compared the file with one of his, and we ended up commenting out three lines in the webinoly config file that were not present in his setup:

31:     #open_file_cache_valid 3m;
32:     #open_file_cache max=129485 inactive=5m;
69:     #open_log_file_cache max=1000 inactive=30s valid=1m;

In my other webinoly server, one of the lines was slightly different:

32:    #open_file_cache max=245817 inactive=5m;

This appears to have solved the problem. I haven't seen the errors I was having since then. I wonder what these lines are there for, or how they're generated, or why they differ across two servers?

Hope this is helpful to someone!

Answer 1

Tell me, did you try to fix it before come here?

What did you find in Google about this topic?

Comments

Hi,

Yes, I spent quite some time trying to learn about it. It seems to be a little bit complicated, related to the server or nginx. The error is not consistent, only happening sometimes. It seems that most people said it was related to not enough space on the drive (I have plenty of space, though). This is the most comprehensive answer, from stack exchange:

https://stackoverflow.com/questions/33867014/what-does-err-spdy-protocol-error-mean-in-nginx

There seems to be many possible causes, and I thought maybe it was something someone here has knowledge of -- maybe a fix on the server would help solve this issue, which I haven't had in the past.

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Most of the times is not related to the server or nginx, as you said. The main reason is due to people using outdated browsers that doesn't support modern protocols. But, as you said, there are to many possible causes.

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We have the latest version of Firefox. Well, we'll see how it goes moving forward. Thanks for the help as always.

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If you find a solution, please share it here, so other members can read about it.

Regards.

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Still no luck finding an answer that is consistent -- it can be not enough disk space, malformed headers, http2 settings -- I couldn't make it work. My user was using Beaver Builder and she could not edit pages some of the time. The errors were happening randomly, sometimes not.

This error occurred on both of my Webinoly servers at different providers (Google Cloud and Hetzner).

I moved her site to another host and it works perfectly now.

I really want to find out what is causing this, so I can trust my server is functioning properly, so hoping someone has some info on this.