Receiving an error Zabbix 111 connection refused?

Often, this error happens due to firewall block or because of the bad settings in the Zabbix config file.

At Bobcares, we often get requests from our customers to fix the Zabbix 111 connection refused as part of our Server Management Services.

Today, we’ll see the reasons and how our Support Engineers fix this error.

How to fix the error Zabbix 111 connection refused?

At Bobcares, where we have more than a decade of expertise in managing servers, we see many customers face problems while managing Zabbix.

Now, let’s see the major reasons for this Zabbix related errors and how our Support Engineers fix the top errors.

Firewall restrictions

A firewall is a network security system that monitors and restricts the incoming and outgoing network traffic based on certain security rules. Most of the users have a firewall on their system to block unauthenticated connections to the server.

However, it may sometimes cause trouble by blocking even the authenticated connection. So, it is necessary to open the required port and adding server IP to the firewall settings.

For example,

One of our customers installed Zabbix-agent on a Windows host, while the Zabbix-server on CentOS host. But he received a value error: cannot connect to [[x.x.xx.x]:10050]: [111] Connection refused.

So, our Supported Engineers tried disabling the firewall temporarily and found that Zabbix was working on the server without any error. So, we made the necessary tweaking in the firewall settings and solved the error.

That’s it.

Incorrect Zabbix settings

Similarly, another customer received the error when he tried to run the command 'systemctl restart zabbix-agent'. He was using Zabbix 3.2.6 on CentOS 7.3.1611.

3816:20170523:111111.975 active check configuration update from [127.0.0.1:10051] started to fail (cannot connect to [[127.0.0.1]:10051]: [111] Connection refused)

On checking, our Supported Engineers found an incorrect setting in the agent configuration file /etc/zabbix/zabbix_agentd.conf. He had set up an entry ServerActive=127.0.0.1. This created the problem.

Therefore, we commented out the line #ServerActive=127.0.0.1 from the agent configuration file /etc/zabbix/zabbix_agentd.conf. Also, we added the Zabbix server IP address.

Server= <server ip>

This is how we fixed the error.

[Having trouble with Zabbix related errors? We’ll fix it for you.] 

Conclusion

In today’s article, we learned that Zabbix 111 connection refused error can occur due to firewall block or because of the bad settings in the Zabbix config file. Today, we saw how our Supported Engineers fixed this error.