SQLSTATE[HY000] [2002] php_network_getaddresses: getaddrinfo for mysql failed: Temporary failure in name resolution
<pre>An Error occurred while handling another error:
yii\web\HeadersAlreadySentException: Headers already sent in /var/www/html/wu888/api/common/components/ComponentsConfig.php on line 43. in /var/www/html/wu888/vendor/yiisoft/yii2/web/Response.php:369
Stack trace:
#0 /var/www/html/wu888/vendor/yiisoft/yii2/web/Response.php(342): yii\web\Response-&gt;sendHeaders()
#1 /var/www/html/wu888/vendor/yiisoft/yii2/web/ErrorHandler.php(136): yii\web\Response-&gt;send()
#2 /var/www/html/wu888/vendor/yiisoft/yii2/base/ErrorHandler.php(152): yii\web\ErrorHandler-&gt;renderException(Object(yii\web\HeadersAlreadySentException))
#3 [internal function]: yii\base\ErrorHandler-&gt;handleException(Object(yii\web\HeadersAlreadySentException))
#4 {main}
Previous exception:
yii\web\HeadersAlreadySentException: Headers already sent in /var/www/html/wu888/api/common/components/ComponentsConfig.php on line 43. in /var/www/html/wu888/vendor/yiisoft/yii2/web/Response.php:369
Stack trace:
#0 /var/www/html/wu888/vendor/yiisoft/yii2/web/Response.php(342): yii\web\Response-&gt;sendHeaders()
#1 /var/www/html/wu888/vendor/yiisoft/yii2/base/Application.php(390): yii\web\Response-&gt;send()
#2 /var/www/html/wu888/frontend/web/index.php(17): yii\base\Application-&gt;run()
#3 {main}</pre>