Custom key solves the problem of inaccurate Zabbix port monitor value

Today, a friend asked me a question about Zabbix monitoring TCP port, obviously the port is listening, but the value taken by Net.tcp,listen is 0. After a simple Goole discovery, this has been a long-standing problem: The root cause of the problem is that the Zabbix key (Net.tcp,listen) is being collected by reading the/proc/net/tcp file, and/proc/ File is not thread-safe, so there is a problem with inaccurate values.      In addition, this mechanism has another hidden danger: When the/proc/net/tcp file has a lot of entries, it will result in a slow value, so it is possible to cause the problem of value failure. Then we should solve this problem, the Internet has found a solution, I am here when the nature of the Porter ~ Haha solution is to add a new user-defined key to replace the Zabbix to provide their own monitoring method, the specific steps are as follows: #1, add a custom key---net.tcp.listen.grep[*]Add the following configuration in the Agentd configuration file for the Zabbix client, or in the Include profile directory declared by Zabbix Agentd:

Userparameter=net.tcp.listen.grep[*],grep-q $$ (printf '%04x.00000000:0000.0a ' $)/proc/net/tcp && echo 1 | | Echo 0

For example, my choice is in the/ETC/ZABBIX/ZABBIX-AGENTD.CONF.D directory, created a file net_tcp_listen.conf, the above key to write the declaration to the file, because my zabbix_ The configuration file directory contains the declarations that have been made in agentd.conf:

thatsit:~ # grep ^include/etc/zabbix/zabbix-agentd.confinclude=/etc/zabbix/zabbix-agentd.conf.d/thatsit:~ #thatsit : ~ # Cat  /etc/zabbix/zabbix-agentd.conf.d/net_tcp_listen.confuserparameter=net.tcp.listen.grep[*],grep-q $$ ( printf '%04x.00000000:0000.0a ' $/proc/net/tcp && echo 1 | | Echo 0thatsit:~ #

#2, restart the zabbix-agentd for the configuration to take effect

shipeng:~ #/etc/init.d/zabbix-agentd restartshutting down Zabbix agentd donestarting Zabbix                                              agentd                                                   doneshipeng:~ #

#3, test with Zabbix_get

thatsit:~ # zabbix_get-s 192.168.3.154-k "net.tcp.listen.grep[22]" 1thatsit:~ # zabbix_get-s 192.168.3.154-k "NET.TCP.L ISTEN.GREP[23] "0thatsit:~ #

#4, on the web side, add this monitoring item to the pointing host.

The key of the monitoring item is:net.tcp.listen.grep[the port number to monitor]

#5, configuration complete, troubleshooting ideas

This configuration has been completed, if there is a problem, you can follow the following ideas to troubleshoot, the general problem in the log can be found in the clues.

# Troubleshooting Ideas:There are a few things to note when adding a key: Note the owner or group configuration of a configuration file or custom script if you use a custom script, note that if you need to execute a custom script, you also need to open the following parameter in zabbix_agentd.conf:

thatsit:~ # grep ^unsafe/etc/zabbix/zabbix-agentd.confunsafeuserparameters=1thatsit:~ #

Reference Link: http://www.oschina.net/question/224285_128311

Custom key solves the problem of inaccurate Zabbix port monitor value