User-friendly error pages from Varnish

Question

We are using Varnish at the front of Plone. In the case Plone goes down or serves an internal error we\'d like to show a user-friendly static HTML page which some CSS styling +

Answer 1

If you rather prefer to deliver an error page from a static file, you can override vcl_error() with a bit of C-code:

sub vcl_error {
    set obj.http.Content-Type = "text/html; charset=utf-8";

    C{
        #include 
        #include 

        FILE * pFile;
        char content [100];
        char page [10240];
        char fname [50];

        page[0] = '\0';
        sprintf(fname, "/var/www/error/index.html", VRT_r_obj_status(sp));

        pFile = fopen(fname, "r");
        while (fgets(content, 100, pFile)) {
            strcat(page, content);
        }
        fclose(pFile);
        VRT_synth_page(sp, 0, page, "", vrt_magic_string_end);

        return (deliver);
    }C
}