Re: A cache problem of some sort?
Hi.
On Sat, Nov 30, 2019 at 07:56:19AM -0600, Richard Owlett wrote:
> On 11/30/2019 07:17 AM, Reco wrote:
> > Hi.
> >
> > On Sat, Nov 30, 2019 at 07:00:51AM -0600, Richard Owlett wrote:
> > > I have a problem with
> > > [https://www.nia.nih.gov/health/sample-menus-healthy-eating-older-adults]
> > >
> > > In the 2nd paragraph it says "The U.S. Department of Agriculture’s ChooseMyPlate offers sample 2-week menus."
> > >
> > > There is a bad link labeled "sample 2-week menus". It links to
> > > [https://www.choosemyplate.gov/budget-sample-two-week-menus].
> > > {apparently should go to https://www.choosemyplate.gov/sites/default/files/2WeekMenusAndFoodGroupContent.pdf}
> >
> > Same thing here. Whatever they fixed did not include that page, as it
> > is served with Last-Modified header set to Wed, 20 Nov 2019 17:51:50 GMT
> >
>
> Thank you. I hadn't realized I could check the "Last-Modified header". I get the same information. I had reported the problem on 11/22/2019.
>
> I'm not an expert in the detailed "structure" of the internet.
> What's the likelihood of we both going through thru something "cache like" when accessing the website?
It's more simple and complex than that.
First (a simple part),
$ host www.nia.nih.gov
www.nia.nih.gov is an alias for d17do31n0bvj2b.cloudfront.net.
... <4 ipv4 here, 8 ipv6> ...
It's highly likely that the problematic page is served by several
independent instances of Apache (HTTP headers do not specify exact
version), and some of those serve updated content, but some of those do
not.
To be specific, 2600:9000:20ae:7400:16:fb03:50c0:93a1 serves outdated
content as demonstrated by Last-Modified header.
Second (a complex part), response headers contain these:
X-Cache: Hit from cloudfront
Via: 1.1 <gibberish>.cloudfront.net (CloudFront)
X-Amz-Cf-Pop: HEL50-C1
X-Amz-Cf-Id: <base64_gibberish>
Apparently www.nia.nih.gov utilizes Amazon reverse proxy. Whenever it's
a caching proxy (and a possible part of this problem), or not (so it's
only the Apache that's broken) - that I cannot say.
My small experience with reverse proxies is limited to nginx.
Reco
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