[[["易于理解","easyToUnderstand","thumb-up"],["解决了我的问题","solvedMyProblem","thumb-up"],["其他","otherUp","thumb-up"]],[["很难理解","hardToUnderstand","thumb-down"],["信息或示例代码不正确","incorrectInformationOrSampleCode","thumb-down"],["没有我需要的信息/示例","missingTheInformationSamplesINeed","thumb-down"],["翻译问题","translationIssue","thumb-down"],["其他","otherDown","thumb-down"]],["最后更新时间 (UTC):2025-09-04。"],[],[],null,["# Troubleshoot origins\n\nThis page shows you how to resolve issues with [origins](/media-cdn/docs/origins)\nwhen you configure them to work with Media CDN.\n\nTroubleshoot origin connectivity\n--------------------------------\n\nIf you are receiving HTTP 50x errors, such as HTTP 502 (Gateway Timeout) or HTTP\n500 (Internal Server Error), consider the following:\n\n- Test that the origin hostname can be resolved with [Google Public\n DNS](http://dns.google.com/), and that the resolved IP addresses matches\n expectations. If you recently changed your DNS records, resolvers might\n still have the old address in their caches.\n\n- If your origin *only* supports HTTP/1.1 and does not support HTTP/2,\n configure the `protocol` field on the origin to use `HTTP` or `HTTPS`\n instead of `HTTP2`. Media CDN does not fall back to HTTP/1.1\n connections unless specified.\n\n- Check that [request logs in Cloud Logging](/media-cdn/docs/logging)\n contain the correct origin IP address.\n\n- Check that origin has a valid (publicly trusted) and unexpired SSL (TLS)\n certificate.\n\n- HTTP/2 Trailers are not supported, and requests to an origin\n server don't include the \"TE\" request header. Trailers included in a\n response are not cached or returned to the client.\n\nTroubleshooting origin failover\n-------------------------------\n\nIf an origin failover isn't behaving as expected, consider the following:\n\n- Ensure that the appropriate host header rewrite is configured on your\n failover origin.\n\n- Ensure that your primary origin is configured with sufficient\n `maxAttemptsTimeout`, `maxAttempts`, and `timeouts` to accommodate origin\n redirects and failovers. Origin redirects count as separate connection\n attempts against the `maxAttempts` setting.\n\nWhat's next\n-----------\n\n- Read about [origin connectivity and shielding](/media-cdn/docs/origins)"]]