我正在尝试从cloudfront访问我的ALB。但是出现502错误。 如果有帮助，请找到以下日志：
#Fields: date time x-edge-location sc-bytes c-ip cs-method cs(Host) cs-uri-stem sc-status cs(Referer) cs(User-Agent) cs-uri-query cs(Cookie) x-edge-result-type x-edge-request-id x-host-header cs-protocol cs-bytes time-taken x-forwarded-for ssl-protocol ssl-cipher x-edge-response-result-type cs-protocol-version fle-status fle-encrypted-fields
2019-07-30 13:51:07 NRT57-C2 1463 124.213.43.8 GET dgrr1986pvy9n.cloudfront.net / 502 - Mozilla/5.0%2520(Windows%2520NT%252010.0;%2520Win64;%2520x64;%2520rv:68.0)%2520Gecko/20100101%2520Firefox/68.0 - - Error RwaT_FUAmnByJ0aNSmdD7rHA298CHhhY6La-Pg2KTKCwBCXTgkWFWw== dgrr1986pvy9n.cloudfront.net https 21 0.027 - TLSv1.2 ECDHE-RSA-AES128-GCM-SHA256 Error HTTP/2.0