在配置号eureka注册中心后，启动前端页面时出现：
前端页面：
FreeMarker template error (DEBUG mode; use RETHROW in production!): The following has evaluated to null or missing: ==> replica.key [in template "eureka/navbar.ftlh" at line 68, column 62] ---- Tip: It's the step after the last dot that caused this error, not those before it. ---- Tip: If the failing expression is known to legally refer to something that's sometimes null or missing, either specify a default value like myOptionalVar!
后端控制台出现：
freemarker.runtime : Error executing FreeMarker template freemarker.core.InvalidReferenceException: The following has evaluated to null or missing: ==> replica.key [in template "eureka/navbar.ftlh" at line 68, column 62]...
原因是当时我写的yml文件中url写错
defaultZone:${eureka.instance.hostname}:${spring.application.name}:${server.port}/eureka
修改为：可以正常显示
defaultZone: http://localhost:8761/eureka #单机版服务注册中心