I am using wordpress. I deploy Varnish Using Docker. This Is My default.vcl. What's Wrong With This Config?? Sometimes, Get Random 503 Error. I Exclude Wordpress Search Page Using RegEx. Also Get Random 503 Error On wordpress Search Page Too!!

varnishlog

https://www.dropbox.com/s/ruczg2i3h/log.txt

I am Using NGINX Backened.. Help Appreciated Thanks

Your log output contains the following lines:

-   Error          out of workspace (bo)
-   LostHeader     Date: 
-   BerespHeader   Server: Varnish
-   VCL_call       BACKEND_ERROR
-   LostHeader     Content-Type:
-   LostHeader     Retry-After:

Apparently you ran out of workspace memory because the size of the response.

The following parameters in your Docker config might cause that:

-p http_resp_hdr_len=65536 \
-p http_resp_size=98304 \

While increasing the size of individual headers and the total response size, the total memory consumption exceeds the workspace_backend value, which defaults to 64k.

Here's the documentation for http_resp_size:

$ varnishadm param.show http_resp_size
http_resp_size
        Value is: 32k [bytes] (default)
        Minimum is: 0.25k

        Maximum number of bytes of HTTP backend response we will deal
        with.  This is a limit on all bytes up to the double blank line
        which ends the HTTP response.
        The memory for the response is allocated from the backend
        workspace (param: workspace_backend) and this parameter limits
        how much of that the response is allowed to take up.

As you can see, it affects workspace_backend. So here's the documentation for that:

$ varnishadm param.show workspace_backend
workspace_backend
        Value is: 64k [bytes] (default)
        Minimum is: 1k

        Bytes of HTTP protocol workspace for backend HTTP req/resp.  If
        larger than 4k, use a multiple of 4k for VM efficiency.

        NB: This parameter may take quite some time to take (full)
        effect.

The solution is to increase the workspace_backend through a -p runtime parameter.