Hi, still related to the previous post, but put simply: I'd just appreciate to learn how to keep Apache from automatically adding "User-Agent" to the "Vary" header. thank you in advance On Thu, Oct 22, 2015 at 11:51:31PM -0300, Raphaël Droz wrote: > I recently received a dozens of AH00708: errors in my logs. > Example: > > (2)No such file or directory: AH00708: Cannot open data file /var/cache/apache2/mod_cache_disk/Y/Z/CLVvRR_4nNWabdUv_5wA.header.vary/B/z/bK@xxxxxxxxxxxxxxxxxxxxxx > > Said file does not exist, only does the corresponding .header file. > The cache is 455 MB, I don't know what could have happened and I > activated debug loglevel for mod_cache_disk for next days in order to > understand why the data file isn't created. > > ... but, looking at the header file I found the following line rather > strange: > [...] > > Content-Encoding: gzip > > Vary: User-Agent, User-Agent, User-Agent, User-Agent > > Accept-Ranges: byte > [...] > > - I've no occurrence of Vary either in /var/www nor in /etc/apache2 > - searching google retrieved a couple of similar results of this Vary: string > > The origin is probably the BrowserMatch directive which, by default are > enabled in Debian's mods-available/setenvif.conf. > (and mod_ssl depends upon mod_setenvif) > > This is how I realized that the cache coupled to setenvif in it's > default configuration was *very* inefficient (disk-space). > `Vary: User-Agent` is something we would rather avoid given the > ridiculously huge number of combination for this string nowadays. > From the last quick grep' I had 325 of them what could reduce my cache's > size to a dozens of MB and increase proportionally it's efficiency. > > > First, not really a question, but a couple of suggestions: > - BrowserMatch should not blindly add to the Vary header but > addifnotexist (it's part of the mod_headers possibility in Apache 2.4 > series isn't?) > - mod_cache_disk documentation could state whether this duplication hurts or not > - the default setenvif.conf may avoid use of "exotic"/"rare" default > BrowserMatch directives in case of <IfModule mod_cache.c> > > > > ... but then, following the objective to avoid a Vary: User-Agent, I > found that I had two other BrowserMatch in default-ssl.conf. > The second one about MSIE 7 to 10, in order to set ssl-unclean-shutdown. > - I didn't find where is documented what this variable does internally > - I guess this variable only affects mod_ssl behavior but nothing about > request header/data > If the above is right, then is it pertinent with discard^W Vary: > User-Agent if the content can't change according to the User-Agent. > Maybe BrowserMatch could be more flexible about that. > > Anyway, I commented these two mod_ssl BrowserMatch directives (in case I > would not care about broken? MSIE behaviors), but I'm still Vary'ing: > User-Agent. > > I commented the ultimate SetEnvIfExpr my configuration contained > (unrelated to browsers anyway) and egrep -ri '(Browser|SetEnvIf)' > but still... Vary: User-Agent > https://github.com/apache/httpd/search?l=c&q=User-Agent&type=Code&utf8=%E2%9C%93 > didn't brought up another clear source for this. > > Any hint about where this Vary's value could come from? > > > thank you > -- GPG id: 0xF41572CEBD4218F4 --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscribe@xxxxxxxxxxxxxxxx For additional commands, e-mail: users-help@xxxxxxxxxxxxxxxx
|