Auto changing interface from IP to DNS (bug?)

[artsiom82]

Hello everybody
Friends, please tell me, for no reason, via some proxies, the zabbix agent interface begins to be monitored via DNS, by itself. No settings were changed. Hostinterface isn`t written in the config ... What can be checked?
zabbix 5.4.5 and also proxies
We localized the problem, but we cannot understand what the problem is,
Configured auto-registration action (pic attached)
using auto-registration the server is registered (pic attached)
If auto-registration is not turned off, then after a while another interface is added, "connect via" changes to DNS and becomes the default (pic attached)
and of course the server stops being monitored.
At the same time, if you disable auto-registration, then everything is ok, but in this case, new servers, respectively, will not be registered
friends, please give me options for where to dig, very similar to a bug ...

[Hamardaban]

покажите конфиг на агенте.

[artsiom82]

покажите конфиг на агенте.

LogFile=c:\windows\zabbix\zabbix_agentd.log
LogFileSize=1
EnableRemoteCommands=1
Server=192.168.100.249
ServerActive=192.168.100.249
UserParameter=product_state,wmic /NAMESPACE:\\root\SecurityCenter2 PATH AntiVirusProduct GET /value | find "productState"
UserParameter=display_name,wmic /NAMESPACE:\\root\SecurityCenter2 PATH AntiVirusProduct GET /value | find "displayName"
UserParameter=ZScript[*],powershell c:\windows\zabbix\zabbix_helper\windows.$1.ps1 "$2" "$3"
Hostname=SRV_M 7A4A594A

[Hamardaban]

ничего криминального....
а не включено ли обнаружение устройств в сети ?
и нет ли в присоединенных шаблонах дискавери интерфейсов?

[artsiom82]

ничего криминального....
а не включено ли обнаружение устройств в сети ?
и нет ли в присоединенных шаблонах дискавери интерфейсов?

1.не включено обнаружение
2. Не совсем понимаю о каких Вы интерфейсах говорите. Если Вы имеете в виду "Правила обнаружения", то такие есть, например с ключем "vfs.fs.discovery"

[artsiom82]

Anybody? Any help please...

[aigars.kadikis]

Please have a look at how the proxy is sending the auto registration data to the central server. Run this in the proxy database:

SELECT FROM_UNIXTIME(clock),host,listen_ip,listen_port,li sten_dns,host_metadata,flags,tls_accepted FROM proxy_autoreg_host ORDER BY clock ASC;
The meaning of columns:

id	id	Unique record ID Table ids is used as indicator of sent records
clock	time	Unix timestamp when host was discovered
host	varchar(64)	Retrieved host name from active agent request
listen_ip	varchar(39)	Host IP address
listen_port	integer	Host port
listen_dns	varchar(255)	Resolved host DNS name from IP address
host_metadata	varchar(255)	Metadata, as sent by the agent It is based on HostMetadata or HostMetadataItem configuration parameters
tls_accepted	integer	Type of incoming connection used for autoregistration: 1, HOST_ENCRYPTION_NONE - Unencrypted (default) 2, HOST_ENCRYPTION_PSK - TLS with PSK The values of this column are a subset of values of 'tls_accept' column in 'hosts' table.
flags	integer	Type of connection to the host 0, ZBX_CONN_DEFAULT - connect using IP address, don't update host interface 1, ZBX_CONN_IP - connect using IP address, update default host interface 2, ZBX_CONN_DNS - connect using DNS name, update default host interface

I suspect the last column 'flags' in your situation will start sending number '2':

2, ZBX_CONN_DNS - connect using DNS name, update default host interface
Please confirm.

If this is the case, we will move to the agent side troubleshooting.

[aquablast.rus]

This is a zabbix bug.

In my case, only one host from the entire list of hosts controlled by the proxy caused the entire list of 450 hosts to switch to the dns connection itself. This was the only host where the HostInterface parameter was specified in the agent configuration.

To fix it, I removed this parameter from the agent configuration and changed the value of the flags field of the proxy_autoreg_hosts table to 0 on proxy database. After that, there were no automatic switching of the interface connection to dns.

Zabbix version 5.4.11 for server and all of proxies.