zabbix监控中会在多处用到宏变量（macros），这会使配置更方便简洁有效。

zabbix支持的宏变量有很多，官网文档支持列表：

https://www.zabbix.com/documentation/2.0/manual/appendix/macros/supported_by_location#zabbix本身支持的宏变量

Macros with numbers <1-9> like {MACRO1}, {MACRO2}…{MACRO9} allow to reference hosts in the order in which they appear in a trigger expression. So, {HOST.IP1} and {HOST.IP2} will expand to the IPs of the first and second host in the trigger expression.
#宏变量可以和数字合用，表示主机在触发器表达式中出现的顺序位置

在自动发现中使用的宏有固定的语法：{#MACRO}

这种宏用于low-leveldiscovery中可以返回真正的文件系统名字，网络接口，以及snmpOIDs

Some low-level discovery macros come “pre-packaged” with the LLD funtion in Zabbix - {#FSNAME}, {#FSTYPE}, {#IFNAME}, {#SNMPINDEX}, {#SNMPVALUE}. However, adhering to these names is not compulsory when creating a custom low-level discovery rule. Then you may use any other LLD macro name and refer to that name.

对于更大的灵活性，zabbix支持用户自定义的宏，这些自定义的宏也有特定的语法：{$MACRO}

宏的级别有多种：其优先级如下。

1.host level macros (checked first)#主机级别的宏优先级最高
2.macros defined for first level templates of the host (i.e., templates linked directly to the host), sorted by template ID#第一级模板中的宏
3.macros defined for second level templates of the host, sorted by template ID#第二级模板中的宏
4.macros defined for third level templates of the host, sorted by template ID
5.…
6.global macros (checked last)#全局级别的宏

#总结：如果在主机级别不存在宏设置，那么zabbix就会去模板中看是否设置有宏。如果模板中也没有，将会查找使用全局的宏。
#若是在各级别都没找到宏，将不使用宏
#创建自定义宏的步骤是：
管理---一般--宏（定义全局宏）
模板和主机在创建时会有设置宏的地方
If a user macro is used in items or triggers in a template, it is suggested to add that macro to the template even if it is defined on a global level. That way, exporting the template to XML and importing it in another system will still allow it to work as expected.

通常使用宏的地方：

1.taking advantage of templates with host specific attributes: passwords, port numbers, file names, regular expressions, etc
2.global macros for global one-click configuration changes and fine tuning

#举例：
Use of host-level macro in the “Status of SSH daemon” item key:
net.tcp.service[ssh,{$SSH_PORT}]
This item can be assigned to multiple hosts, providing that the value of {$SSH_PORT} is defined on those hosts.
Example 2
Use of host-level macro in the “CPU load is too high” trigger:
{ca_001:system.cpu.load[,avg1].last(0)}>{$MAX_CPULOAD}
Such a trigger would be created on the template, not edited in individual hosts.
If you want to use amount of values as the function parameter (for example, max(#3)), include hash mark in the macro definition like this: SOME_PERIOD  #3
Example 3
Use of two macros in the “CPU load is too high” trigger:
{ca_001:system.cpu.load[,avg1].min({$CPULOAD_PERIOD})}>{$MAX_CPULOAD}
Note that a macro can be used as a parameter of trigger function, in this example function min().
User macros in a trigger expression will be expanded if referencing a parameter or a constant. They are NOT supported for referencing the host name, item key, function or operator.

宏和正则表达式：