Welcome to WebmasterWorld Guest from 54.147.63.124

Forum Moderators: Ocean10000 & incrediBILL & phranque

Message Too Old, No Replies

Etags in apache headers

what are they, what are best settings?

     
5:05 am on Oct 1, 2003 (gmt 0)

Senior Member

WebmasterWorld Senior Member 10+ Year Member

joined:Dec 16, 2002
posts:2010
votes: 0


I noticed one of my shared hosting server just started showing Etags in the headers
example:
ETag "1e40c7-4f2f-3f78f85d"

I found this documentation to control them (not sure if htaccess can override the httpd.conf in this case)
[httpd.apache.org...]

but I don't completely understand how browsers/proxies use them?

Stuff like this only confuses me further:
[studio.tellme.com...]

Thanks for any help!

4:26 pm on Oct 1, 2003 (gmt 0)

Senior Member

WebmasterWorld Senior Member 10+ Year Member

joined:Sept 21, 1999
posts:2141
votes: 0


I don't either! But this from the Apache directive you linked to:
The ETag value is used in cache management to save network bandwidth.
I'm inclined to think that it will be up to each browser/proxy to decide if or how to use ETags. Perhaps some "conventions" will or have emerged as to their use but I have no idea where to look or how to find them.

From your other link:

An ETag is an HTTP response header returned by an HTTP/1.1 compliant Web server such as Apache 1.3x.
ETags are "new." They first became available with the HTML/1.1 spec.
4:35 am on Oct 2, 2003 (gmt 0)

Senior Member

WebmasterWorld Senior Member 10+ Year Member

joined:Dec 16, 2002
posts:2010
votes: 0


More research shows they are appearing when I use the mod_expires directive.

Apache must auto-integrate the two (or my host has some options doing this).

Etags seem to show the file size and time as an origination stamp, so maybe the proxies/caches can determine when to update if they ignore the expires info?

Oh and apparently I *can* override their display and format in htaccess.