egg http request

使用egg自帶的curl的時候，間歇性會報錯，為什么？

at errnoException (dns.js:50:10)
at GetAddrInfoReqWrap.onlookup [as oncomplete] (dns.js:92:26)
code: "ENOTFOUND"
errno: "ENOTFOUND"
syscall: "getaddrinfo"
hostname: "test.com"
host: "test.com"
port: 80
name: "RequestError"
data: undefined
path: "/test"
status: -1
headers: {}
res: {"status":-1,"statusCode":-1,"headers":{},"size":0,"aborted":false,"rt":5,"keepAliveSocket":false,"requestUrls":["http://test.com/test"],"timing":null,"remoteAddress":"","remotePort":"","socketHandledRequests":1,"socketHandledResponses":0}
pid: 23297