Zabbix Agent on different subnet

[zabbixW32]

This scenario in Windows environment. I have an issue when monitoring agent in different subnet (DMZ). Is this something that can be done by Zabbix? All agents in same subnet as Zabbix server are fine.

Nothings blocking in firewall (allow all), I don't see any drop/reject packet either.
On agent log (Active Chaeck cannot connect to zabbix_server_ip:10051 no error)
On server log (cannot connect to[ zabbix_agent_hostname] connection refused)

I am not using active check, which work just fine the in same subnet.
I move a client from different subnet to same subnet as server, it works just fine.

I can ping vice-versa from server-client. I can SMB it too.

Anyone have same issue?

Thanks alot.

[peter_field]

Can you telnet?

Can you telnet to port 10051 on the server from the client?
What about the other way, from the server to the client on port 10050?

Make sure your clients zabbix_agentd.conf has the correct IP of the server listed, i.e. Server=x.x.x.x, but I imagine that is right if it works when you move the PC to the other subnet.

Are you referring to the server by name? If so does it resolve properly in the other subnet?

[dantheman]

How about in the logs on the server and the host, do they give you any idea what is or isnt' going on?

[zabbixW32]

Thank you for the feedback.
I list the server-client by IP address.
telnet are not allow, but on the same subnet (server-client) works just fine with that.

The log on the server:
Cannot connect to [Hostname] [Connection refused]
That [Hostname] is the name of HOST which I type in I create a new Host in Zabbix, which is not necessarily same with machine name.

The log on the client side: almost nothing, what I can see is:
Active Check cannot connect to [zabbix_server_ip:10051 ][no error]
That zabbix_server_ip is xxx.xxx.xxx.xxx

I don't use Active Check, this error will not show up if I bring the client in to same subnet (change the IP) as server.

Is this setting can be done:

zabbix server

|

|

Switch-----Router/Firewall-----Switch-----zabbix Client

|

|

zabbix client

The bold works (windows server 2003 SP1,XP SP2)
The italic not works no matter the OS.

Thanks alot

[Calimero]

Thank you for the feedback.
I list the server-client by IP address.
telnet are not allow, but on the same subnet (server-client) works just fine with that.

If
server$ telnet <clientip> 10050
or
client$ telnet <serverip> 10051
don't work, your firewall is probably misconfigured.

[zabbixW32]

I misread the post from peter_field (thought telnet:23) just realized after reading Calimero's post.
Thanks all btw.

Yes I can telnet either way on same or different subnet.

if I do netstat on client in same subnet, I see listenning on port 10050, then a bunch of time_wait for connection to zabbix server.
on different subnet, I only see listenning on port 10050.

I see previous post:

http://www.zabbix.com/forum/archive/index.php/t-516.html

looks similar, but not understand about "use sender"

[zabbixW32]

Fixed the issue

We had this issue fixed a month ago. We ran ethereal on server and client and saw the NAT issue between DMZ and internal network.

Thanks for all the feedback.