The connection to Zabbix server "localhost" failed

[CDThibaut]

Hello,
I created a new zabbix server on Zabbix 5, the sql server and the application are on two separate servers. When I log into the web interface, I have the error:

The connection to Zabbix server "localhost" failed. Possible reasons:
• 1. Incorrect server IP / DNS in "zabbix.conf.php";
• 2. Incorrect DNS server configuration.
• Connection refused

Zabbix server is running on CentOS 8, SELinux is disabled and the firewall too

The zabbix server service is running:

zabbix-server.service - Zabbix Server
Loaded: loaded (/usr/lib/systemd/system/zabbix-server.service; enabled; vendor preset: disabled)
Active: active (running) since Mon 2020-08-10 09:57:53 CEST; 7s ago
Process: 339749 ExecStop=/bin/kill -SIGTERM $MAINPID (code=exited, status=0/SUCCESS)
Process: 339830 ExecStart=/usr/sbin/zabbix_server -c $CONFFILE (code=exited, status=0/SUCCESS)
Main PID: 339832 (zabbix_server)
Tasks: 1 (limit: 49770)
Memory: 2.9M
CGroup: /system.slice/zabbix-server.service
└─339832 /usr/sbin/zabbix_server -c /etc/zabbix/zabbix_server.conf

Here is the content of the zabbix.conf.php :

<?php
// Zabbix GUI configuration file.

$DB['TYPE'] = 'MYSQL';
$DB['SERVER'] = 'bddserver';
$DB['PORT'] = '3306';
$DB['DATABASE'] = 'zabbix';
$DB['USER'] = 'user';
$DB['PASSWORD'] = 'xxx';

// Schema name. Used for PostgreSQL.
$DB['SCHEMA'] = '';

// Used for TLS connection.
$DB['ENCRYPTION'] = true;
$DB['KEY_FILE'] = '';
$DB['CERT_FILE'] = '';
$DB['CA_FILE'] = '';
$DB['VERIFY_HOST'] = true;
$DB['CIPHER_LIST'] = '';

// Use IEEE754 compatible value range for 64-bit Numeric (float) history values.
// This option is enabled by default for new Zabbix installations.
// For upgraded installations, please read database upgrade notes before enabling this option.
$DB['DOUBLE_IEEE754'] = true;

$ZBX_SERVER = 'localhost';
$ZBX_SERVER_PORT = '10051';
$ZBX_SERVER_NAME = '';

$IMAGE_FORMAT_DEFAULT = IMAGE_FORMAT_PNG;

// Uncomment this block only if you are using Elasticsearch.
// Elasticsearch url (can be string if same url is used for all types).
//$HISTORY['url'] = [
// 'uint' => 'http://localhost:9200',
// 'text' => 'http://localhost:9200'
//];
// Value types stored in Elasticsearch.
//$HISTORY['types'] = ['uint', 'text'];

// Used for SAML authentication.
// Uncomment to override the default paths to SP private key, SP and IdP X.509 certificates, and to set extra settings.
//$SSO['SP_KEY'] = 'conf/certs/sp.key';
//$SSO['SP_CERT'] = 'conf/certs/sp.crt';
//$SSO['IDP_CERT'] = 'conf/certs/idp.crt';
//$SSO['SETTINGS'] = [];

Does anyone have any idea where the problem is?

[CaveatL]

In zabbix.conf.php, the below variable:

$ZBX_SERVER = 'localhost';

should reference the IP address of the Zabbix Server (not localhost).

[sewet]

Hello,

I know this is an old post but how do you save the config file after editing?

Thanks