[[["容易理解","easyToUnderstand","thumb-up"],["確實解決了我的問題","solvedMyProblem","thumb-up"],["其他","otherUp","thumb-up"]],[["難以理解","hardToUnderstand","thumb-down"],["資訊或程式碼範例有誤","incorrectInformationOrSampleCode","thumb-down"],["缺少我需要的資訊/範例","missingTheInformationSamplesINeed","thumb-down"],["翻譯問題","translationIssue","thumb-down"],["其他","otherDown","thumb-down"]],["上次更新時間:2025-07-31 (世界標準時間)。"],[],[],null,["# Migrating an Existing Service\n\nThis guide shows how to prepare a web service to run in a container on\nKnative serving. It does not cover data migration.\n\nIdentify the port your code is listening on\n-------------------------------------------\n\nYour service should listen for requests on a specific port. You must identify\nthis port and [configure Knative serving to send request to the same port](/kubernetes-engine/enterprise/knative-serving/docs/configuring/containers#command-line).\n\nThis is the same port you would use when invoking your service on your local\nmachine. For example, if to test your code you open `localhost:3000`, then [set\nthe container port](/kubernetes-engine/enterprise/knative-serving/docs/configuring/containers#command-line) to\n`3000` in Knative serving.\n\nKnative serving defaults to sending requests to `8080`.\nThe value of the port to which requests are sent is always available in the\n`PORT` environment variable. It is a best practice for your code to listen on\nthe value defined by the `PORT` environment variable if possible.\n\nRemove reliance on local filesystem for persistent storage\n----------------------------------------------------------\n\nCheck your application code for reliance on local filesystems, and replace it\nwith file storage on [Cloud Storage](/storage) or data storage such as\n[Firestore](/firestore) or [Cloud SQL](/sql).\n\nAdd a `Dockerfile`\n------------------\n\nIn order to wrap your service in a container, you should use a Dockerfile to\ndefine the operating environment. Read more about customizing your `Dockerfile`\non the [Developing your service](/kubernetes-engine/enterprise/knative-serving/docs/developing#add-dockerfile)\npage.\n\nTune for concurrency and memory limits\n--------------------------------------\n\nLearn about [concurrency](/kubernetes-engine/enterprise/knative-serving/docs/concurrency) in\nKnative serving and how to optimize your services in\n[development tips for tuning concurrency](/kubernetes-engine/enterprise/knative-serving/docs/tips/general#tuning-concurrency).\n\nMake sure your [memory limit](/kubernetes-engine/enterprise/knative-serving/docs/configuring/memory-limits) is high enough\nfor your application to run, including capacity for any temporary file storage\nyour service requires.\n\nSend logs to stdout or stderr\n-----------------------------\n\nKnative serving automatically uses Google Cloud Observability to aggregate and\nreview your logs, as described in the [logging page](/kubernetes-engine/enterprise/knative-serving/docs/logging)."]]