环境：
服务端 ip ：192.168.1.204 hostname：www.test.com
服务端 ip ：192.168.1.206 hostname：www.test3.com
1、查看zabbix_server日志
20477:20181210:031034.692 cannot send list of active checks to "127.0.0.1": host [Zabbix server] not found
20477:20181210:031048.065 cannot send list of active checks to "192.168.1.206": host [Zabbix server] not found
20515:20181210:031234.832 cannot send list of active checks to "127.0.0.1": host [Zabbix server] not found
20494:20181210:031248.193 cannot send list of active checks to "192.168.1.206": host [Zabbix server] not found
20514:20181210:031434.949 cannot send list of active checks to "127.0.0.1": host [Zabbix server] not found
20514:20181210:031448.334 cannot send list of active checks to "192.168.1.206": host [Zabbix server] not found
20478:20181210:031634.075 cannot send list of active checks to "127.0.0.1": host [Zabbix server] not found
2、解决
2.1、修改zabbix_server和客户端的hosts
服务端：
[mysql@www ~]$ sudo cat /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.1.204 www.test.com
192.168.1.206 www.test3.com
客户端：
[root@www ~]# cat /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.1.204 www.test.com
192.168.1.206 www.test3.com
2.1、修改zabbix客户端配置文件里面Hostname
sed -i 's/Hostname=Zabbix server/Hostname=www.test.com/g' /usr/local/zabbix/etc/zabbix_agentd.conf
2.3、重启这两台机器
2.4、重启zabbix_server 、zabbix_agent（必须）
2.5、测试下载东西，然后刷新浏览器，看zabbix的流量图是否发生变化
wget http://mirrors.aliyun.com/centos/7.6.1810/isos/x86_64/CentOS-7-x86_64-DVD-1810.iso
不要用ping -l 65500 192.168.1.206 ping是测试不出来的
2.6、用火狐浏览器打开zabbix，然后设置火狐浏览器自动刷新网页，就会时刻看到发生的变化
3、调整zabbix_server参数
3.1、按照下面修改
vi /usr/local/zabbix/etc/zabbix_server.conf
StartPollers=160
StartPollersUnreacheable=80
StartTrappers=20
StartPingers=100
StartDiscoverers=120
Cachesize=1024M
startDBSyncers=16
HistoryCacheSize=1024M
TrendCacheSize=1024M
HIstoryTextCacheSize=512M
3.2、重启zabbix_server
参照文档：
https://blog.csdn.net/wang725/article/details/80790400