Last-Modified header is not being added in page response from dispatcher.

[Umesh_Thakur]

Dear Members,

I was analysing the network call for a page, one very unique kind of issue I observed that is :

Not able to see the last-modified header for page content, for other type like dam, clientlibs fonts an all I can can the header in the same network call.

First I thought this my be the reason that publisher is not sending the header but when I see the *.html.h file, the last-modified header was present in the dispatcher cached file. sam as other types like dam n all.

I explicitly try to send the same response header thru. a custom filter but again no luck.

Try to see the behaviour after commenting all the Rewrite rules but agin no luck.

Note: there is no Header unset for those two headers either direct or conditional.

Same thing is working in my local dispatcher and apache .

Please suggest if anyone is having some thought about the root cause.

Thanks

Umesh Thakur

[antoniom5495929]

Hi Umesh,

are you sure that there's no CDN (like Akamai) on top of your dispatcher?

Cause it could happens that Akamai it's configured only for dispatch some specific header (without last-modified).

Let us know,

Thanks,

Antonio

[Umesh_Thakur]

Thanks for your response Antonio.

This is only for dispatcher there is no CDN involved.

--Umesh Thakur

[antoniom5495929 · Accepted solution]

HI @Umesh_Thakur ,

have you the possibility to perform a curl into the dispatcher server?

You should try to execute from the dispatcher server the following curl:

curl --head http://serverip/page-of-aem

and check if head appears into this list.

Based on the result we can be sure if the issue happens cause of a dispatcher configuration issue or not.

Let us know.

Thanks,

Antonio

[milind_bachani]

Hi @Umesh_Thakur ,

Are there any headers listed under /cache /headers in the dispatcher ?

/cache
     -/headers

Thanks.

[Umesh_Thakur]

Yes Milind, we have allowed caching for those headers and being cached as well but not appending as part of the response header. 

Thanks for the response.

Umesh Thakur

[Jörg_Hoh]

You need to enable "Header Caching" on the dispatcher, see https://experienceleague.adobe.com/docs/experience-manager-dispatcher/using/configuring/dispatcher-c...

Jörg

[Umesh_Thakur]

Thanks for the response @Jörg_Hoh ,

It is already enabled and Last-Modified header is being cached as well but not appending in the response.

I can see the header in as response header in other content type like dam assets, css n all but not able to see only for page content.

We don’t have any rule written to unset the header for page content .

Please guide

Thanks

Umesh Thakur

[Jörg_Hoh]

So to recap:

* In the dispatcher cache there is a page.html.h file present, containing the relevant header informatino.

* but when you request this page.html via curl from the dispatcher, these headers are not part of the response.

In this case I would recommend to set the loglevel to 3 to get the maximum amount of logging and then redo the request. 

[Umesh_Thakur]

Yes, you are right @Jörg_Hoh,

not even in browser response header I can see the last-modified header for page content.

I tried with loglevel 3 as well not much info. Please see the below images for curl and its generated log:

curl:

 

log:

Thank you very much

Umesh Thakur

[Jörg_Hoh]

Can you check with a full GET? Not sure if HEAD requests have the full set of response headers. Can you also check if there's a difference when you request from your development machine and from localhost (that means being logged on the same machine where the dispatcher runs and doing the same request via localhost)?

[serhii_kovalenko1]

@Umesh_Thakur @Jörg_Hoh 

hi, i have the same issue, the Last-Modifed header is saved in test.html.h but it's not added to the request's response to the page. did you resolve this issue on you end?