Article in joomla 3.5.1 on Data center server not getting saved

we have upgraded the PHP from 5.3.3 to 5.6.18.. we are uable to save the articles.
Expected result

when we click save and close., system should save the article on the Dc SITE server and should show in the
pick list of the articles.

Issue Still there...
Actual result

the connection has timed out
System information (as much as possible)

RED HAT ENTERPIRSE LINUX 6
APACHE SERVER 2.2.15
PHP 5.6.18