虽然 AlloyDB Auth Proxy 可以监听任何端口，但它只会在端口 5433 上创建与 AlloyDB 实例的传出或出站连接。如果您的客户端主机具有出站防火墙，则必须允许连接到 AlloyDB 实例 IP 地址上的端口 5433。客户端主机还必须允许与所有 IP 地址的端口 443（标准 HTTPS 端口）建立连接。
AlloyDB Auth Proxy 如何授权 IAM 主账号
如需授权客户端连接到 AlloyDB 实例，Auth Proxy 客户端会使用客户端上的 IAM 主账号凭据向 Google Cloud 进行身份验证，然后验证 IAM 主账号是否具有 Cloud AlloyDB Client (roles/alloydb.client) 和 Service Usage Consumer (roles/serviceusage.serviceUsageConsumer) IAM 角色。
如需在客户端上找到 IAM 凭据，Auth Proxy 客户端会检查是否存在以下各项，并使用找到的第一项尝试向 Google Cloud进行身份验证：
[[["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)：2025-08-25。"],[[["\u003cp\u003eThe AlloyDB Auth Proxy enables secure, encrypted connections to AlloyDB databases using IAM-based authorization.\u003c/p\u003e\n"],["\u003cp\u003eIt provides advantages over direct connections by using IAM credentials for authorization and establishing TLS 1.3 encrypted connections with a 256-bit AES cipher.\u003c/p\u003e\n"],["\u003cp\u003eThe Auth Proxy runs a local client that communicates with the application using standard database protocols and establishes connections to AlloyDB via secure tunnels.\u003c/p\u003e\n"],["\u003cp\u003eThe Auth Proxy automatically manages and refreshes ephemeral SSL certificates, which expire every 24 hours.\u003c/p\u003e\n"],["\u003cp\u003eThe AlloyDB Auth Proxy supports various methods for locating IAM credentials, including service account JSON key files, OAuth 2.0 access tokens, environment variables, gcloud CLI credentials, and Compute Engine instance credentials.\u003c/p\u003e\n"]]],[],null,["# About the AlloyDB Auth Proxy\n\nThis page provides an overview of the AlloyDB Auth Proxy, a connector that lets you\nmake authorized, encrypted connections to AlloyDB\ndatabases.\n\nFor a step-by-step guide to using the Auth Proxy, see [Connect using the AlloyDB Auth Proxy](/alloydb/docs/auth-proxy/connect).\n\nBenefits of using the AlloyDB Auth Proxy\n----------------------------------------\n\nThe Auth Proxy provides these advantages over connecting clients directly to\nAlloyDB databases:\n\n- **IAM-based connection authorization (AuthZ):** The Auth Proxy uses\n the credentials and permissions of an Identity and Access Management (IAM) principal to authorize connections to\n AlloyDB instances.\n\n- **Secure, encrypted communication:** The Auth Proxy automatically\n creates, uses, and maintains a TLS 1.3 connection\n using a 256-bit AES cipher\n between your client and an AlloyDB instance to verify client\n and server identities and encrypt data traffic.\n\nFor more information about to connecting to AlloyDB instances,\nsee [Connection overview](/alloydb/docs/connection-overview).\n\nHow the AlloyDB Auth Proxy works\n--------------------------------\n\nThe AlloyDB Auth Proxy works by having a local client running\nin the local environment. Your application communicates with the AlloyDB Auth Proxy\nwith the standard database protocol used by your database.\n\nThe AlloyDB Auth Proxy uses a secure tunnel (TLS 1.3,\n256-bit AES cipher) to\ncommunicate with its companion process\nrunning on the server. Each connection established through the AlloyDB Auth Proxy creates\none connection to the AlloyDB instance.\n\nWhen an application connects to the AlloyDB Auth Proxy, it checks whether an existing\nconnection between it and the target AlloyDB instance is available.\nIf a connection does not exist, it calls AlloyDB Admin APIs to obtain\nan ephemeral SSL certificate and uses it to connect to AlloyDB.\nEphemeral SSL certificates expire in 24 hours. The AlloyDB Auth Proxy refreshes\nthese certificates before they expire.\n\nThe AlloyDB Auth Proxy calls APIs through the domain name `alloydb.googleapis.com`\nusing HTTPS. As a result, all egress TCP connections on port 443 (HTTPS) from\nthe client machine must be allowed by your firewall.\n\nWhile the AlloyDB Auth Proxy can listen on any port, it creates outgoing or egress\nconnections to your AlloyDB instance only on port 5433. If your client\nhost has an outbound firewall, it must allow connections to port 5433 on your\nAlloyDB instance's IP address. The client host must also allow\nconnections to port 443, which is the standard HTTPS port, to all IP addresses.\n\nHow the AlloyDB Auth Proxy authorizes IAM principals\n----------------------------------------------------\n\nTo authorize a client's connection to an AlloyDB instance, the\nAuth Proxy client authenticates to Google Cloud using IAM principal\ncredentials on the client, and then validates that the IAM principal has the\nCloud AlloyDB Client (`roles/alloydb.client`) and Service Usage Consumer\n(`roles/serviceusage.serviceUsageConsumer`) IAM roles.\n\nTo locate the IAM credentials on the client, the Auth Proxy client checks\nfor each of the following items, using the first one it\nfinds to attempt authentication to Google Cloud:\n\n1. **Credentials supplied by the --credentials-file flag**\n\n Use a [service account](/alloydb/docs/auth-proxy/best-practices#using-a-service-account) to\n create and download the associated JSON key file, and set the\n `--credentials-file` flag to the path of the file when you start\n the Auth Proxy client.\n The service account must have the Cloud AlloyDB Client\n (`roles/alloydb.client`) and Service Usage Consumer\n (`roles/serviceusage.serviceUsageConsumer`)\n IAM roles for the AlloyDB instance.\n\n To use this option on the command-line, invoke the `alloydb-auth-proxy` command with\n the `--credentials-file` flag set to the path and filename of a JSON credential\n file. The path can be absolute, or relative to the current working directory.\n2. **Credentials supplied by the --token flag**\n\n [Create an\n access token](https://developers.google.com/oauthplayground/) and invoke the `alloydb-auth-proxy` command with the\n `--token` flag set to an OAuth 2.0 access token.\n3. **Credentials supplied by an environment variable**\n\n This option is similar to using the `--credentials-file` flag, except you specify\n the JSON credential file you set in the `GOOGLE_APPLICATION_CREDENTIALS` environment\n variable instead of using the `--credentials-file` flag.\n4. **Credentials from an authenticated Google Cloud CLI client**\n\n If you installed the [gcloud CLI](/sdk/gcloud)\n and have authenticated with your personal account, the Auth Proxy client\n can use the same account credentials if you enable the\n `--gcloud-auth` flag. This method is especially helpful for\n getting a development environment up and running.\n | To enable the Auth Proxy client to use your gcloud CLI credentials, use the `gcloud auth login` command to authenticate the gcloud CLI. To determine your current gcloud CLI credentials, use the `gcloud auth list` command.\n\n If no account was selected for `gcloud auth login`, the\n Auth Proxy client checks for an account that was selected for `gcloud\n auth application-default login`. This is the default behavior when you\n don't enable the `--gcloud-auth` flag.\n5. **Credentials associated with the Compute Engine instance**\n\n If you are connecting to AlloyDB from a Compute Engine instance, the\n Auth Proxy client can use the service account associated with the Compute Engine instance.\n If the service account has the Cloud AlloyDB Client\n (`roles/alloydb.client`) and Service Usage Consumer\n (`roles/serviceusage.serviceUsageConsumer`)\n Identity and Access Management (IAM) roles for the AlloyDB instance, the Auth Proxy client\n authenticates successfully.\n\n If the Compute Engine instance is in the same project as the AlloyDB\n instance, the default service account for the Compute Engine instance has the\n necessary permissions for authenticating the AlloyDB.\n If the two instances are in different projects, you must add the Compute Engine\n instance's service account to the project containing the AlloyDB\n instance.\n6. **Environment's default service account**\n\n If the Auth Proxy client cannot find credentials in any of the places covered earlier, it\n follows the logic documented in\n [Authenticating as a service account](/docs/authentication/production).\n Some environment (such as Compute Engine, App Engine, and others) provide a\n default service account that your application can use to authenticate by default. If\n you use a default service account, it must have the Cloud AlloyDB Client\n (`roles/alloydb.client`) and Service Usage Consumer\n (`roles/serviceusage.serviceUsageConsumer`) IAM roles.\n\n For more information about Google Cloud's approach to authentication, see\n [Authentication overview](/docs/authentication).\n\nWhat's next\n-----------\n\n- [Connect using the AlloyDB Auth Proxy](/alloydb/docs/auth-proxy/connect).\n- [Explore the Google Cloud GitHub repository for the AlloyDB Auth Proxy](https://github.com/GoogleCloudPlatform/alloydb-auth-proxy)."]]
