Opengraph image not showing on linked-in when using https

Hi there,

Our website is completely accessible through https and our Apache uses a rewrite rule to redirect every http-request to https. Everything works fine except that linked-in does not show the open graph image that is defined by JFBConnect when I try to share a link to our website. All other social networks that I have tested (Facebook, Twitter, Google+) work fine with https. As a work-around I have modified the rewrite rule in Apache so that http-requests coming from linked-in bot are not rewritten - with this the og:image works if addressed through http by linked-in. But the big disadvantage of this is that users can not easily share articles on our website, because they always use https-requests.
Funny enough a rewrite-rule that rewrites https-requests coming from linked-in bot to http does not have any effect on this issue.

Do you have any idea what could cause this problem?

Regards,
Axel

Hi Alex,

Thanks for your reply. All the og:image links are indeed https and I know that other https-sites work well with LinkedIn. But strange enough, our website www.comex.eu does not and I have no idea what causes this.
For easier testing without having troubles with the cache of linked-in I have created 5 URLs that you can use:
www.comex.eu/test1
www.comex.eu/test2
www.comex.eu/test3
www.comex.eu/test4
www.comex.eu/test5
but of course any other URL on our website shows the same effect, if they have an og:image tag (did not yet put a default image in the configuration).

Here is our standard-rewrite rule for https, at the moment the special LinkedIn part is disabled:
# Rewrite all to https - except LinkedIn
RewriteCond %{HTTPS} off
#RewriteCond %{HTTP_USER_AGENT} !linkedinbot [NC]
RewriteRule ^(.*)$ https://%{HTTP_HOST}/$1 [L,R=301]

If I enable the LinkedIn part "RewriteCond %{HTTP_USER_AGENT} !linkedinbot [NC]" http requests coming from LinkedIn are not rewritten and I can correctly share articles if I use the http-link in LinkedIn.

Funny enough the problem is only with LinkedIn. Facebook, Twitter and Google+ show no problems.

Regards,
Axel

Hi,

I finally found what the problem was: if in Apache's ssl-config file (in our case default-ssl) ServerName or ServerAlias are not set or do not match the name on the SSL-certificate, the server sends an "Unrecognized Name"-warning. This warning is ignored by nearly every client (browsers, facebook, search engine bots, ...) but the LinkedIn bot stops loading.

Although Twitter ignores this warning and displays correctly, you can use the Twitter card validator (cards-dev.twitter.com/validator) to check for this issue, because it throws an error message. Or you use Wireshark to listen on ip-traffic but for this particular issue the Twitter card validator is easier and good enough.

Best regards,
Axel