Forum Discussion

Brian_Brehart's avatar
Brian_Brehart
Icon for Altostratus rankAltostratus
Feb 18, 2020

Compression stripped by Silverline

We've recently experienced slowdowns serving web pages, and here's something we've found:

Apparently, when traffic passes through the WAF, the WAF strips out the following line: Content-Encoding: gzip. We serve pages compressed with GZIP, but, from what we can see, the WAF strips that compression, severely slowing down the page delivery. Does this make sense to anyone, and is there a way to remediate this issue?

 

 

compression
F5 Cloud Services
gzip
security
Silverline
  • Aaronb's avatar
    Aaronb
    Icon for Employee rankEmployee
    Mar 12, 2020

    F5 Silverline inserts a Via header in all HTTP requests sent to back-end web servers.

    • However, some web servers do not compress data if a request contains a "Via" header.
    • This can lead to longer load times for clients as well as increased bandwidth usage.

    Please consult your server documentation for details. 

    IIS server:

    https://docs.microsoft.com/en-us/iis/troubleshoot/performance-issues/troubleshooting-iis-compression-issues-in-iis6-iis7x

    appcmd set config -section:system.webServer/httpCompression /noCompressionForHttp10:"False" /noCompressionForProxies:"False" /commit:apphost

    NGINX

    https://nginx.org/en/docs/http/ngx_http_gzip_module.html#gzip_proxied

    Syntax: gzip_proxied off | expired | no-cache | no-store | private | no_last_modified | no_etag |auth | any ...;

    Default:

    gzip_proxied off;

    Context: http, server, location

  • NUT2889's avatar
    NUT2889
    Icon for Cirrostratus rankCirrostratus
    Feb 24, 2020

    Hi,

     

    You can open ticket to F5 Silverline team. TAC team will immediatly help you to identity the problem.