Error: cannot send list of active checks to [x.x.x.x]: host [SAFLOK-PC] not found

[NE1Scott]

These are almost all Linux machines.or WinSRV2008R2 machines

In the linux config file I see this set :
ServerActive=127.0.0.1
Hostname=Zabbix server

The IP of my Zabbix server is really the only thing in this file I was told to set. (Whole config file shown sans comments)

Hostname=Zabbix server
Include=/etc/zabbix/zabbix_agentd.d/*.conf
LogFileSize=0
LogFile=/var/log/zabbix/zabbix_agentd.log
PidFile=/var/run/zabbix/zabbix_agentd.pid
Server=XXX.XXX.XXX.XXX (obfuscated on purpose
ServerActive=127.0.0.1


In the Zabbix configuration ftab GUI for this host the following is set :

Host name Prod_OANIS_UK2-O13-CZS1AOS
Visible name
Groups PROD_VicDel_Limeric

Interfaces Type IP address DNS name Connect to Port Default
Agent 172.31.13.133 IP 10050

Obviously my obfuscated actual machine name is UK2-O13-CZS1AOS.hhu.local

[cyber]

ServerActive=127.0.0.1
Hostname=Zabbix server

These suit only zabbix servers own agent config.

On any other host

ServerActive=<your zabbix server/proxy IP, probably same as in Server= field>
Hostname=<your hosts name>

in you case "Prod_OANIS_UK2-O13-CZS1AOS" as this is already configured in GUI.

OR, you can set "UK2-O13-CZS1AOS.hhu.local" as hostname in agent config and in GUI and set "visible name" to "Prod_OANIS_UK2-O13-CZS1AOS" in GUI

[NE1Scott]

I may have forgotten to mention that I don't believe we are using active checks.
I could be wrong but due routing and firewall issues we started everything off just using "Template OS Linux by Zabbix agent" and NOT "Template OS Windows by Zabbix agent active".

If this is the case how can I disable the active checks since I am getting between 3 and 6 logs per second like :

21860:20220520:191251.181 cannot send list of active checks to "172.16.52.249": host [UK-O13-VHS1.hhu.local] not found
21856:20220520:191252.632 cannot send list of active checks to "172.16.52.149": host [UK2-O13-ADCB.hhu.local] not found
21860:20220520:191253.434 cannot send list of active checks to "172.16.52.177": host [UK-O13-DFS2.hhu.local] not found
21859:20220520:191253.683 cannot send list of active checks to "172.16.52.114": host [UK2-O13-IWS365A] not found
21858:20220520:191254.117 cannot send list of active checks to "172.16.52.127": host [UK-O13-CWS8] not found
21858:20220520:191256.534 cannot send list of active checks to "172.16.52.12": host [UK-XDI-WSUS1.xdihosting.corp] not found
21856:20220520:191258.413 cannot send list of active checks to "172.16.52.47": host [UK-XDI-AMS2.xdihosting.corp] not found
21860:20220520:191258.631 cannot send list of active checks to "172.16.52.75": host [UK2-O13-CSARTBAP] not found
21860:20220520:191259.926 cannot send list of active checks to "172.16.52.125": host [UK2-O13-CWS6.hhu.local] not found
21860:20220520:191300.060 cannot send list of active checks to "172.16.52.213": host [UK-XDI-CSA4] not found
21859:20220520:191300.272 cannot send list of active checks to "172.16.52.122": host [UK2-O13-CWS3.hhu.local] not found
21856:20220520:191300.425 cannot send list of active checks to "172.16.52.111": host [UK2-O13-ADFS2.hhu.local] not found
21857:20220520:191301.330 cannot send list of active checks to "172.16.52.150": host [UK-XDI-CDS1] not found
21856:20220520:191301.367 cannot send list of active checks to "172.16.52.153": host [UK-XDI-CDS1B.xdihosting.corp] not found
21857:20220520:191302.038 cannot send list of active checks to "172.16.52.84": host [UK-O13-CDS1BOS.hhu.local] not found
21859:20220520:191302.277 cannot send list of active checks to "172.16.52.245": host [UK-O13-VHS2.hhu.local] not found
21856:20220520:191305.039 cannot send list of active checks to "172.16.52.118": host [UK-O13-IWS365B] not found
21856:20220520:191307.918 cannot send list of active checks to "172.16.52.104": host [UK-O13-IWS2.hhu.local] not found
21859:20220520:191308.506 cannot send list of active checks to "172.16.52.166": host [UK2-O13-CDS1BAP.hhu.local] not found
21856:20220520:191310.412 cannot send list of active checks to "172.16.52.160": host [UK2-XDI-DIVA1.xdihosting.corp] not found

And while yes most of them do not have the hostname properly configured as we discussed above, I am not sure what is generating these active checks in the first place.

[Markku]

The error message means that you have configured the agents with ServerActive=<zabbix-server-or-proxy> (= the agents are trying to connect "back home" and get the active checks to execute). In that case you need to have the matching host created in Zabbix server, otherwise you get these errors.

Markku

[idhamhafidz]

I understand that my zabbix agent was meant to be passive. So I just comment the HostName. All the logs go away

[mrnobody]

Comment line of your agent conf

#ServerActive=<ip_or_host>

Restart agent service and be happy with only passive checks and no active errors on log