HOST NOT FOUND

[rolfrolf]

hello,

i just updated a zabbix proxy of a customer to the version 5.0 because i have uüdated our zabbix server to 5.0.
Now i have a problem that one specific host cant connect and it gets the error "HOST NOT FOUND".
I already reinstalled the agent on the server and on the customer machine.
Connections have been checked via telnet and are working. Hostname is the same in the config file as in the zabbix server gui.
Agent is on version 5.0, proxy is on 5.0 and server is on 5.0.
Services have been restarted multiple times already.

hope someone can help

[LenR]

Sounds like a DNS problem, where is the error, on the client or server? Check the host name (dns or ip) on the host interface.

[rolfrolf]

The Client is added via ip address which I checked is correct.
On the Client I have the Same error.
Can’t send active checks because Host not found.

[Hamardaban]

Mismatch of the Hostname in the agent config and the hostname in the host settings on the server.

https://www.zabbix.com/documentation/current/manual/appendix/config/zabbix_agentd

Hostname

no

Set by HostnameItem

List of comma-delimited unique, case-sensitive hostnames. Required for active checks and must match hostnames as configured on the server. Value is acquired from HostnameItem if undefined. Allowed characters: alphanumeric, '.', ' ', '_' and '-'.

[rolfrolf]

No the Client hostname in the config file and in the Server are identical