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26 votes

Setting X-Forwarded-Proto under Apache 2.4

It's correct to set this directive like RequestHeader set "X-Forwarded-Proto" expr=%{REQUEST_SCHEME} RequestHeader set "X-Forwarded-SSL" expr=%{HTTPS} If it doesn't work, you may need to install and ...
spaceone's user avatar
  • 361
24 votes

Difference between the Accept and Content-Type HTTP headers

Accept is like Here is my request and I would like (to Accept) this response format Content-Type is like Here is my request (or response) and this (Content-Type) is the format of the content ...
JRomio's user avatar
  • 341
10 votes
Accepted

How is HTTP 418 treated by Google and others as it is not a "real" error?

If you use the "Fetch as Google" tool in Google Search Console on a page that returns a "418 I'm a Teapot" status then it simply reports an "Error" and indexing cannot be ...
MrWhite's user avatar
  • 42.8k
8 votes

Difference between the Accept and Content-Type HTTP headers

It is a request-response conversation, so the client sends a request of "Content-Type" and expects to receive the response of "Accept" media type.
Waldemar's user avatar
8 votes
Accepted

Why does it cause issues to use robots.txt and a meta robots tag at the same time?

The robots.txt standard controls whether the bot can view foo.html under any circumstances. Just because the bot sees a link to it from a different site doesn't give the bot permission to sneak a peek ...
Maximillian Laumeister's user avatar
7 votes

Headers to prevent 304/If-modified-since/HEAD requests

What you want is the immutable keyword in your Cache-Control line. Example for php: header('Cache-Control: public, max-age=80000, immutable'); Source: https://code.facebook.com/posts/557147474482256/...
Zdenek's user avatar
  • 256
6 votes

X-Robots-Tag: noindex on an HTTP 302 response to remove subdomain

As of December 2022, Google will respect a X-Robots-Tag HTTP Response header that comes as part of a HTTP 302 response - Google Search Console will report: "Indexing allowed? No: 'noindex' ...
Roberto Tyley's user avatar
6 votes
Accepted

Will it hurt SEO to remove the '.html' extension from static pages such that they get served as 'text/x-generic'?

This isn't so much an SEO issue, as an issue as to whether your site would work at all. If it doesn't work in the browser then it's certainly going to hurt your SEO. Your HTML pages still need to ...
MrWhite's user avatar
  • 42.8k
5 votes

If i use 301 redirects (to bounce the requests), will the other destination be aware of my Server IP?

Well aren't you friendly... "Hey Google, I'm having a DOS, but im making it your problem, thanks" First: There is no difference for you between serving an 301 or an 404 error page. Your ...
Martijn's user avatar
  • 6,806
5 votes
Accepted

What headers used in request by google bot?

if ($_SERVER['HTTP_CACHE_CONTROL'] == 'no-cache') { Also bear in mind that the Cache-Control HTTP request header (as with most request headers) are entirely optional, so may not be present as part of ...
MrWhite's user avatar
  • 42.8k
5 votes
Accepted

What is difference between robots.txt, sitemap, robots meta tag, robots header tag?

While X-Robots-Tag and meta robots are equivalent, robots.txt is different. The former is about indexing, while the latter is about crawling/visiting. Tell bots not to visit a URL by using robots.txt....
Maximillian Laumeister's user avatar
5 votes

Cannot add "Host" header in Cloudfront

Official docs says You can’t configure CloudFront to add any of the following headers to requests that it sends to your origin: Cache-Control Connection Content-Length Cookie Host If-Match If-...
Muhammad Dyas Yaskur's user avatar
4 votes

What is recommended minimum object size for gzip performance benefits?

Apache Tomcat has gzip filter and it starts to zip from 2kb, my quick test tells that it's the lowest boundary, and you can increase it at least to 3-4kb. Because for 2kb you will get a similar size ...
Yura's user avatar
  • 141
4 votes
Accepted

Looking for explanation of Apache behavior on manipulating headers

how this workaround indeed works PHP runs later in the request, so most of the time you can simply override any headers that Apache has already set in your PHP code. That's pretty much it. (Aside: ...
MrWhite's user avatar
  • 42.8k
4 votes
Accepted

CSP3 Report-To header implementation

There are examples in the draft of the Reporting-Endpoints directive: Reporting-Endpoints = endpoint-1="https://example.com/reports" Your rule is correctly created, as in it returns a valid ...
Braiam's user avatar
  • 210
3 votes

Setting X-Forwarded-Proto under Apache 2.4

Those response headers you are seeing look fine. You should not expect to the X-Forwarded-Proto header in them. As you state, that header is set when the request is proxied to the back end. To ...
Stephen Ostermiller's user avatar
3 votes

X-Robots-Tag: noindex on an HTTP 302 response to remove subdomain

Google considers the status code before looking at everything else, so the X-Robots-Tag will be ignored. We did some test a year ago with a client and this was not working. The strategy that we used ...
brclz's user avatar
  • 181
3 votes

Is no cache meta tag bad for performance?

Using a no-cache meta tag is a bad idea. Page caching is valuable for both SEO and user experience. Caching will improve (lower) page load times. This means a user sees the content faster, which ...
James Hobson's user avatar
3 votes

Website <head> section questions

The order of meta tags does not make a difference. You can use both ' and " in html5. The conditional comments can be useful if you want to create specific CSS for Internet Explorer 8. However in ...
Osvaldo's user avatar
  • 2,379
3 votes

Why does Pingdom suggest that I add a "Vary: Accept-Encoding" header?

What is it? The Vary HTTP response header tells user agents (clients) that the server's response can vary if the client changes any of the mentioned request headers. Vary: Accept-Encoding This means ...
Oskar Skog's user avatar
3 votes

Do browsers send different HTTP headers on page reload so that server side caches can be flushed?

No. The browser will send the same information on a refresh as if the user had just come to that page, with the same referrer information. Hence the problem of double-POSTing if someone refreshes the ...
GeoffAtkins's user avatar
  • 2,277
3 votes
Accepted

Do browsers send different HTTP headers on page reload so that server side caches can be flushed?

Browsers do send additional headers, but behavior different. This info in link a bit outdated: stackoverflow question Looks like Cache-control:no-cache is the best solution, to check for Ctrl+F5, but ...
LeonidMew's user avatar
  • 605
3 votes

Double redirect - referrer in headers

Is it possible to check on the end (3) that user visit came from (1) my shortened link? No, because "(1) my shortened link" is not the referrer. The web page that contains "(1) my ...
MrWhite's user avatar
  • 42.8k
3 votes
Accepted

Should I always use 410 instead of 404?

Search engines (including Google) index neither "404 Not Found" URLs nor "410 Gone" URLs. From an indexing perspective using 410 as the default instead of 404 isn't going to be any ...
Stephen Ostermiller's user avatar
2 votes

Is no cache meta tag bad for performance?

The use of 'to cache or no-cache depends on the end performance sort: 1) Affiliate Marketers - need to 'cache tags' when pages etc go to landing pages as the cookies are needed for allocation of ...
susanlewis's user avatar
2 votes

How to get keywords from Google HTTP referrer?

This website decodes the url for you but there's not too much information in there. https://gqs-decoder.appspot.com/ scheme : http netloc : www.google.sk path : /url params : query : usg : ...
Luen's user avatar
  • 21
2 votes
Accepted

Googlebots request types

I'm pretty sure Googlebot does not send HEAD requests - at least not with respect to crawling and indexing a website. My access logs from January and February 2016 show no HEAD requests from the ...
MrWhite's user avatar
  • 42.8k
2 votes
Accepted

Is it feasible to use Vary: headers with If-none-match: to improve caching?

Based on your question and your clarification comment you would be better served using the URL rather than a header in order to best deal with downstream caching servers. In other words the first time ...
Chris Rutherfurd's user avatar
2 votes
Accepted

When should I not to use page meta security headers

I think you are asking about a conflict between HTTP headers versus page meta elements, correct? If yes, you should use HTTP headers and remove the page meta elements (at least the ones for security) ...
Tom Brossman's user avatar
  • 2,291

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