host name issue

[tagsense]

hello,
i am running a zabbix server and zabbix agent on the same machine. i see that both the processes are running ok and ports are open. i also verified that the messages are coming ok by using netcat.

however, i see that the agentD has the following messages in its log:
15306:20090615:173757 Sending [{
"request":"active checks",
"host":"Zabbix"}]
15306:20090615:173757 Before read
15306:20090615:173757 Got [{
"response":"failed",
"info":"host [Zabbix] not found"}]

and the server log has the following message:
15233:20090615:174157 Send list of active checks to [127.0.0.1] failed: host [Zabbix] not found

btw, i haven't configured the front end as i haven't figured out how to do that. is this error happening because the host name is not defined through front end?

thanks
david

[Calimero]

When active checks are enabled (DisableActive=0 in zabbix_agentd.conf), zabbix_agent will connect to zabbix_server every RefreshActiveChecks seconds (defaults to 120 sec) and ask what checks it should perform. To get the list zabbix_agent gives zabbix_server the client hostname as defined in zabbix_agentd, not the system hostname.

So if zabbix_server doesn't know anything about the given hostname (because you didn't create the corresponding host in DB/GUI), it will tell the requesting client to go die.

[nono77]

Hostname issue bis

Hi everybody,
I have a problem with active check (zabbix 1.6.4) when the lenght of client' hostname is longer than 8 character.
-->No active checks on server: host [qualsurcouf] not found

if i change hostname ( via alias on my DNS) with qsurcouf it's OK
--> Enabling host [qsurcouf]

It's a problem for me because i have a lot of client hostname longer than 8 character.
So , any suggestions .

thank's
sorry for my bad english

[richlv]

if i change hostname ( via alias on my DNS) with qsurcouf it's OK
--> Enabling host [qsurcouf]

that dns reference confused me a bit. in general, for active checks two things should match :

1. hostname as configured in zabbix frontend;
2. hostname as configured in zabbix_agentd config file (make sure to restart agentd after changing this one).

[nono77]

hi,
I talk about hostname of zabbix_agentd not zabbix_server.
If Hostname= (in zabbix_agentd_.conf) is more length than 8 characters , all item Type "ZABBIX agent (active)" don't work.
--No active checks on server: host [123456789] not found -- in zabbix_server.log

if i rename my hostname in zabbix (host) to 123456 and in my zabbix_agentd.conf to "Hostname=123456" I make a alias in my dns server
123456 point to 123456789
I restart my agent zabbix and item Type "ZABBIX agent (active)" is OK

Now i update to 1.6.5 (server+agent) and all is OK even with hostname longer than 8 characters

Thank's for your help

[MrKen]

Hi nono77,

In Zabbix the hostname refers to the name that you decide to call it in configuration of hosts. The hostname has nothing to do with dns.
In the gui, configuration of hosts, you will see Name, DNS, IP, Port, etc.., the name can be anything that you want to call it. Btw I have hostnames that are more than 20 characters in length.

In the zabbix_agentd.conf, Hostname = Zabbix, means that you have a host configured with the name Zabbix (case sensitive). The name Zabbix does not need to resolve dns.

MrKen

[rolandsym]

Something I Discovered

I started to use the windows zabbix installer recently for large deployments and I kept having active checks not working. Long story short, it came to being the order in which I had the server and hostname lines in the config file. If server was first(like in the example) it worked fine but if I put hostname before server than it defaulted to the netbios or hostname of the machine. Which was close to the name but without the domain name info. All this is in the end means make the config file lines in order exactly like the example one.

Hope this helps.

[richlv]

Long story short, it came to being the order in which I had the server and hostname lines in the config file. If server was first(like in the example) it worked fine but if I put hostname before server than it defaulted to the netbios or hostname of the machine.

interesting. do you still see the same behaviour with latest agent ?
if yes, report it on the tracker, thanks.

[rolandsym]

The agent

I was having the deployment automated using the windows installer(not the one from the website). Anyways I would deploy the agent then stop the service, replace the config file, and then start the service again all through a script. I did this with the 1.7.1, 1.6.6, and 1.6.3. They all had the same result. When I swapped hostname and server order active checks started working.
I have not tried this with the www.zabbix.com website pre-compiled one. I'll try later today and see if I get the same results.

Rolandsym

[Nick.Langstone]

alternative solution if zabbix server is behind NAT

As the previous poster noted, you can use SSH to tunnel in, this can be heavy handed sometimes, If you are just going between subnets, or like me the zabbix server is on a VM and is NATed because of stupid network admin rules ...... you can set up a port forwarder on the VM server host so it looks like the zabbix server, and forwards all requests on to the zabbix VM. this is simple an easy.

I use a java port forwarder as it is very light weight and extremely reliable - but there are other port fording solutions.

http://kennethxu.blogspot.com/2006/04/java-based-tcpip-port-forwarding.html

http://code.google.com/p/portforward/

I Hope this helps some one
Nick

[TracePeters]

I see the originally reported error in 1.8.3.

The problem appears to be with the "name field" in the host configuration and how it is parsed. For example, if the 'name field' contains the period character "." then the zabbix-agent reports: No active checks on server: host [badhostnamehere]

If the period character is removed from the host configuration 'name field' then the zabbix-agent can see it.

[richlv]

when adding the dot, do you modify agent configuration file accordingly & restart the agent ?

[TracePeters]

when adding the dot, do you modify agent configuration file accordingly & restart the agent ?

Geeze, I thought I did that but apparently I missed a step! Darn user (me) error.

Thanks for your feedback, restarting the agent did the trick.