defining a host without agent, snmp, jmx nor impi

[Mozai]

I need to monitor a host that I do not have control over, thus I cannot install agent software. All Trigger objects must be associated with an Item object, and all Item objects must be associated with a Host object. But I cannot create a Host object without specifying a Zabbix Agent, or SNMP, or JMX, or IPMI.

If I specify one of these, then Zabbix will keep trying to connect to the (non-existent) agent software of any of these services, and all of the "connection refused" results triggered an alert with the assumption the failures are because I'm trying to hack into the box, and the box shut me out completely.

On the other hand, if I define a special item for some other host, which will monitor the machine that would've locked me out, the dashboard and the triggers will notify people "Machine A is at fault!" when it's really machine B that is unresponsive.

Zabbix advertises agentless monitoring, but it seems that Host objects always assume that there is some agent software (whether it be Zabbix, SNMP, JMX or IPMI), and I cannot create Item objects without a Host object to hang it on.

I wish to create Items (and Triggers) for a machine that I cannot install any agent software into. I believe what I need is a means of creating a Host object without specifying the Zabbix, SNMP, JMX nor IPMI, but the web-based interface will not allow me to do this.

[BDiE8VNy]

A Zabbix host must have at least one host interface configured. But that does not imply to have items of this type or to have items for that host interface at all.
E.g. when there are no Zabbix agent items for an existing Zabbix agent host interface, then Zabbix makes no agent related checks resp. connection attempts.

Further when creating agent-less/simple checks these can be assigned to any existing host interface - regardless of its type

Just create a Zabbix agent host interface and add the desired agent-less checks to it.

ZBXNEXT-1925 requests a kind of dummy host interface. Although for a different use case.

[timbo]

Hi Mozai,

So I am going to assume that you will be sending data from the remote server back to your Zabbix server? Possibly via Zabbix_Sender.exe, or SNMP traps?


I have a similar situation, but I have a host that traps values from multiple machines. Each of these machines play a particular role in interacting with a single distributed application.

So I have one "host" named after the application, and then the other "hosts" are set up as per usual for the servers that interact with the distributed application. So, lets say 1x "virtual host (application)" and 4x "physical hosts (servers)".

This way I can send all the general application health metrics (No. of users, no. txns, etc.) via zabbix_sender.exe to the "virtual host (application)", and all the physical server checks (CPU, RAM, Paging, etc.) to the "physical host (servers)".

All you need to do is under the "Agent interface" section, set the "IP address" to "0.0.0.0", leave DNS name blank and leave the Port as the default.

This is kind of documented (though not too clearly) here:

https://www.zabbix.com/wiki/howto/config/activehost

It seems a little odd to not specify a legitimate IP address, but as far as I have seen Zabbix uses the "Host Name" as the primary identification source, the "Agent interfaces" only seem to be used when you set up an item that explicitly utilises them.

Someone may have a more elegant solution, but this works well for me.

Good luck!

-Timbo

[moses.moore]

A Zabbix host must have at least one host interface configured. But that does not imply to have items of this type or to have items for that host interface at all.
E.g. when there are no Zabbix agent items for an existing Zabbix agent host interface, then Zabbix makes no agent related checks resp. connection attempts.

You said the Zabbix host must have one host interface configured. There is no 'host interface' item in the configuration of a host. The only configuration settings that mention the word interface are these four (which I've already mentioned): Agent interface, SNMP interface, JMX interface, and IPMI interface. Zabbix forbids me from making a host object without defining at least one of these.

If I defined any one of these, Zabbix will frequently check for the presence of an (Agent|SNMP|JMX|IPMI), and these frequent checks will trigger a defensive reaction that will interfere with my work. I've already said this I don't know why I must re-explain this.

Maybe if I added more information: there was a project that we had to out-source because it arrived without enough time for us to complete on our own. The out-sourced company insisted on using technology that we didn't have, so they're hosting it themselves on their own machine, which I don't have root on. However, the services provided by that machine is still our responsibility, so we must monitor it (passively?) that machine and respond quickly if it stops responding (even if all I can do is start phoning people). So, no (Agent|SNMP|JMX|IPMI) interfaces, but I must still do passive monitoring.

It's looking like I'll have to write something of my own to do this monitoring, something entirely separate from Zabbix. Which sucks, and makes me look a bit foolish since I was the one who decided on using Zabbix in the first place. This sort of monitoring was not a problem with Nagios, mon, nor with bigbrother.

Further when creating agent-less/simple checks these can be assigned to any existing host interface - regardless of its type

I already said that attaching a simple check to a separate host will confuse the human who receives the message "There is a problem with host X" when it's actually host Y that has trouble, because I had to attach an Item for host Y onto the Host object for host X. The human will go to host X and look for a problem to solve that isn't there.

So I am going to assume that you will be sending data from the remote server back to your Zabbix server?

I already said "I need to monitor a host that I do not have control over, thus I cannot install agent software," so no, that remote server is not sending data back to the Zabbix server. I also don't have control over the defensive "too many refused connections" reaction, which I want to avoid.

[timbo]

Looks like you're getting a little frustrated there, you do realise we're trying to help don't you?

We both read your post and answered to the best of our ability. BDiE8VNy merely suggested that as long as you don't add passive items, then no traffic will be sent to the IP Address specified under the "Agent interface" section - which sounds right to me. Have you made sure there are no Items that are generating the traffic that's causing the error messages you mentioned. Perhaps remove all Items (and Templates) and start again.

But for arguments sake, let’s assume adding the remote server IP is creating traffic that is presenting you with error messages. Have you tried changing the "IP address" to "0.0.0.0" in the host's "Agent interface" section as I suggested? This will all but ensure no erroneous traffic would get sent to your remote server.

Now, add a "Simple Check" Item like "icmpping[<target>]" - replacing <target> with the desired IP Address (see screenshots attached).

There! You have a "Host" that is not associated with any IP Address (so will not send and "Agent" traffic), and an "Item" that is the only thing that specifies the IP Address of the remote server (which will send ICMP packets from the Zabbix Server to it).

Hope this was helpful.

-Timbo

[moses.moore]

I was getting frustrated. Frustrated enough that I didn't finish reading your message past the stuff that was contrary to what I already said.

Setting one of the interfaces to point at some invalid IP address is an elegant solution for an awkward prerequisite. I'm a little embarrassed I didn't think of this myself. I can hang the simple checks on this Host object without causing confusion nor causing the remote host to bristle defensively.

'0.0.0.0' seems to get replies from 127.0.0.1, but I can point the "Agent interface" property of the Host object to somewhere else in 10.0.0.0/8 or 192.168.0.0/16 and safely expect no hosts will appear later to receive requests.

Thank you.

[timbo]

Also, just referring back to BDiE8VNy suggestion:

Further when creating agent-less/simple checks these can be assigned to any existing host interface - regardless of its type

Zabbix allows you to customise the trigger messages entirely, regardless of the Host the Trigger is set up on.

So you could in fact create the Simple Check Item on a completely separate Host, then create a Trigger on that Host saying "There is a problem with host Y" or X...

So you wouldn't notice if you setup an email/sms trigger on that Item.

The problem with this method is that it makes administration more difficult when you can't remember where you put the Item, and when the Host is reporting a problem on the Zabbix Dashboard (even though the Item may not be perfectly related to the host).

-Timbo