shell-php CentOS on file_get_contents get the domain name on this computer will return false other extranet domain name can be obtained normally

Using file_get_contents on PHP CentOS to get the domain name on this computer will return FALSE for example, a CentOS server is bound with the domain name www.jitapu.me. Getting www.jitapu.me content in PHP will return false.
Like what

Other external domain name can be obtained normally. For example, the above $STR1 returns FALSE, $str 2 returns the normal content.
First firewall should be no problem, or how to access other domain names, the firewall is also access to the 127.0.0.1 port is not limited, MySQL these can be used normally.
I've met this many times. The solution is not to be baffled.

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Using file_get_contents on PHP CentOS to get the domain name on this computer will return FALSE for example, a CentOS server is bound with the domain name www.jitapu.me. Getting www.jitapu.me content in PHP will return false.
Like what

Other external domain name can be obtained normally. For example, the above $STR1 returns FALSE, $str 2 returns the normal content.
First firewall should be no problem, or how to access other domain names, the firewall is also access to the 127.0.0.1 port is not limited, MySQL these can be used normally.
I've met this many times. The solution is not to be baffled.

Ping www.jitapu.me on CentOS and try it out.

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