一台服务器的Zabbix Agent升级后，在Zabbix Server发现Zabbix Agent无法访问。检查Zabbix Agent发现服务停止了，启动Zabbix Agent后，发现服务马上又异常了。遂检查日志发现有下面错误：
26033:20200709:163321.520 Starting Zabbix Agent [xxxx]. Zabbix 5.0.1 (revision c2a0b03480).
26033:20200709:163321.521 **** Enabled features ****
26033:20200709:163321.521 IPv6 support: YES
26033:20200709:163321.521 TLS support: NO
26033:20200709:163321.521 **************************
26033:20200709:163321.521 using configuration file: /etc/zabbix/zabbix_agentd.conf
26033:20200709:163321.530 listener failed: zbx_tcp_listen() fatal error: unable to serve on any address [[-]:10050]
26033:20200709:163321.530 Zabbix Agent stopped. Zabbix 5.0.1 (revision c2a0b03480).