PHP Warning: fwrite() expects parameter 1 to be resource, boolean given in

CENTOS 6 + PHP5要寫入檔案時錯誤
 PHP Warning:  fwrite() expects parameter 1 to be resource, boolean given in

原因是SELINUX要設定開放PHP連接DB
/usr/sbin/setsebool -P allow_url_fopen = 1

Can't connect to MySQL server on 'xxx.xxx.xxx.xxx' (13)

CENTOS 6

PHP 連接mySQL出現Can't connect to MySQL server on 'xxx.xxx.xxx.xxx' (13)

原因是SELINUX要設定開放PHP連接DB
/usr/sbin/setsebool -P httpd_can_network_connect_db=1

SSH金鑰登入

以金鑰做認證登錄

步驟:

 1.ssh-keygen -t rsa (RSA加密) 或 ssh-keygen -d (dsa加密) => 產生公鑰及私鑰 ~./ssh/id_rsa, ~./ssh/id_rsa.pub

 2.scp id_rsa.pub server_hostname:~/.ssh/

 3.ssh server_hostname

 4.cat .ssh/id_rsa.pub >> .ssh/authorized_keys 或 authorized_keys2

 這樣就可以 金鑰認證方式登入, 不需輸入密碼

注意: ssh-keygen 時會問 Enter passphrase (empty for no passphrase): # 此處直接 enter 跳過,下次才不會詢問password

簡單解說一下:

• id_rsa: private key
• id_rsa.pub: public key

將 public key(id_rsa.pub) 拷貝到遠端的電腦後, 加到那 user 的 .ssh/authorized_keys 或 authorized_keys2中.

之後連線時, 就會用本機的 private key(id_rsa) 與遠端電腦的 public key(authorized_keys) 做認證, 確認完成就可以直接登入, 不需輸入帳號密碼

如何查看CentOS版本

# lsb_release -a

# cat /etc/redhat-release