strange error at Zabbix agent

[Umair]

Hello guys,
I have been stuck for quiet some time on this error and would appreciate if some one can give me their valuable advice.

I have an agent installed on a remote machine having a public IP address.
My server is on a private IP address but there is a VPN connection between the two.

In between is ofcourse the router configured for forwarding the request.
When i start the agent, i get the follwong error:

28484:20070629:164845 Listener error: Connection from [<router_ip>] rejected. Allowed server is [<zabbix_server_ip>]

Why is the agent being rejected form the Router?

This is the full error:

28484:20070629:164845 Listener error: Connection from [<router_ip>] rejected. Allowed server is [<zabbix_server_ip>]

28485:20070629:171726 In process_active_checks('192.168.100.45',10051)
28485:20070629:171726 In get_min_nextcheck()
28485:20070629:171726 Sleeping for 60 seconds
28485:20070629:171826 In refresh_metrics('192.168.100.45',10051)
28485:20070629:171826 get_active_checks('192.168.100.45',10051)
28485:20070629:171959 Get active checks error: Cannot connect to [192.168.100.45:10051] [Connection refused]
28485:20070629:171959 Getting list of active checks failed. Will retry after 60 seconds
28485:20070629:172059 get_active_checks('192.168.100.45',10051)
28485:20070629:172059 Get active checks error: Cannot connect to [192.168.100.45:10051] [Connection refused]
28485:20070629:172059 Getting list of active checks failed. Will retry after 60 seconds
28485:20070629:172159 get_active_checks('192.168.100.45',10051)
28485:20070629:172159 Get active checks error: Cannot connect to [192.168.100.45:10051] [Connection refused]
28485:20070629:172159 Getting list of active checks failed. Will retry after 60 seconds
28483:20070629:172257 Processing request.
28483:20070629:172257 In check_security()
28483:20070629:172257 Listener error: Connection from [<router_ip>] rejected. Allowed server is [192.168.100.45]
28485:20070629:172259 get_active_checks('192.168.100.45',10051)
28485:20070629:172259 Sending [ZBX_GET_ACTIVE_CHECKS
localhost
]
28485:20070629:172259 Before read
28485:20070629:172259 In parse_list_of_checks('ZBX_EOF
')
28485:20070629:172259 In disable_all_metrics()
28485:20070629:172259 Parsed [ZBX_EOF]
28485:20070629:172259 In process_active_checks('192.168.100.45',10051)
28485:20070629:172259 In get_min_nextcheck()
28485:20070629:172259 Sleeping for 60 seconds

[Umair]

I would appreciate if someone could give me a clue, as I am unable to determine the cause of the problem.

[Alexei]

Why is the agent being rejected form the Router?

Because your router does network address translation!

[Umair]

Well, as far as i dug out, the Agent does not seem intelligent enough to understand the NAT translations.
I tired pining and it works between the two hosts.
The only possible outcome was the NAT scenario.

Nevertheless, i tried using IP addresses which fall in the same range on both of the machines and it worked.
An agent communication cannot work with private - public IP scheme and vice versa.
Just a conclusion.

[BigSunAdmin]

You can get around this issue. Set an alias to your <router ip> in /etc/hosts, something like "ilovenats". Change the "Server=<zabbixserverip>" your zabbix_agentd.conf file to be "Server=ilovenats".

Create an SSH tunnel between your Zabbix server and your Zabbix client. Restart the Zabbix process and you're good to go.