View Full Version : How Zabbix agent Works ?
1°I need to know how zabbix agent works :confused:
- which protocol does Zabbix agent use to communicate with the server (SNMP,... ?)
- where Zabbix agent found information about the host (/proc/...,Zabbix code ?)
i must build a little "flow chart" to explain zabbix communications
2° i must also compar differences between Zabbix_agent and built-in snmp agent of windows and linux(snmpd)
3° what is the differences between Zabbix_agent and zabbix_agentd
4° have you ever have problems of security with the Zabbix_agent
Thanks for you help.
Linux-specific note. ZABBIX agent must have read-onle access to filesystem /proc. Kernel patches from www.grsecurity.org limit access rights of non-privileged users.
put in little char of the zabbix doc, Zabbix agent certainly take information in the /proc but i am not sure :p
1°I need to know how zabbix agent works :confused:
- which protocol does Zabbix agent use to communicate with the server (SNMP,... ?)
- where Zabbix agent found information about the host (/proc/...,Zabbix code ?)
I cant explain the protocol as I havent poured through the code, but i can give you an overview of the communication process:
zabbix_sender - sends data to zabbix_server
zabbix_agent(d) - listens on the monitored host
zabbix_server:
- queries agent(d) and puts data into database
- listens for data from zabbix_sender and puts into database.
- queries snmp hosts and puts data into database
2° i must also compar differences between Zabbix_agent and built-in snmp agent of windows and linux(snmpd)
Well, windows snmp support is awful. You can get very little out of the stock snmp. You can extend with the stuff from http://www.wtcs.org/snmp4tpc/ but you have to buy the enhanced version. Plus on windows with zabbix you can query any perfmon counter.
On linux snmpd is much better. But having a native agent can provide for better data.
Also, on either platform, zabbix is very extensible.
3° what is the differences between Zabbix_agent and zabbix_agentd
agentd will start, daemonize and listen in the background for connections.
agent must have connection handed to if from (x)inetd.
agentd has a few items that agent does not support. Its generally easier to use than agent.
4° have you ever have problems of security with the Zabbix_agent
I use agentd and have had no problems so far.
HTH
cooper
i have not realy understand agent support more "item" than agentd?
if you are interesse zabbix use simple TCP SYN/SEQ/ACK request .... ( i use Ethereal ) :D
i have not realy understand agent support more "item" than agentd?
From the manual (http://www.zabbix.com/manual_config_items.php, bottom of the page):
"Parameters netload*, disk_read* and disk_write* are supported by zabbix_agentd only. Inetd version of the agent does not support them."
Agentd, supports a few more items than agent.
cooper
disk_read never work i don't understand why because other function work.
did i need an another package to make this features worke or is it an other probleme...
I work with a Debian Sarge 2.6.8 on a laptop
Durring the use of Etherlink I see lot of "Cheksum error" in Zabbix communication is it normal or not ???
can you post zabbix_agentd.log and zabbix_server.log?
zabbix_agents.log
005169:20050302:143735 zabbix_agentd started
005170:20050302:143735 zabbix_agentd 5170 started
005171:20050302:143735 zabbix_agentd 5171 started
005173:20050302:143735 zabbix_agentd 5173 started
005174:20050302:143735 zabbix_agentd 5174 started
005172:20050302:143735 zabbix_agentd 5172 started
Zabbix_server.log is certanly on the zabbix server and i have no access to it.
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If Somebody is interesse i read the source code and i understand that Zabbix_agentd search informations in the /proc/ files
We really need to see the server log. It will show where the disk_read items are queried, and what values are being returned. Without that, I dont have any other ideas.
i read the server log and there is nothing about the disk.
the function disk read status is mark not supported. Did i need a program on my computer (such as hdparm)
the function disk read status is mark not supported. Did i need a program on my computer (such as hdparm)
I dont think so. Alexei, any thoughts?
cooper