Connection terminated due to connection timeout error

Inizia esaminando la configurazione segnalata di TypeORM, pg, Azure Database for PostgreSQL e AKS, quindi confronta il comportamento tra gli SKU Standard_B4ms e Standard_D4as_v5. Analizza lo stack trace del timeout della connessione e la possibile differenza di Azure Accelerated Networking. Il lavoro è completato quando sono state identificate una causa riproducibile e una correzione verificata della configurazione o della dipendenza.

We are using NestJS with TypeORM v0.3.25 and pg v8.11.3

Our TypeOrm config is:

const baseOrmConfig: PostgresConnectionOptions & TypeOrmModuleOptions = {
  type: 'postgres',
  host: process.env.DATABASE_HOST ?? 'localhost',
  port: process.env.DATABASE_PORT !== undefined ? Number(process.env.DATABASE_PORT) : 5432,
  username: process.env.DATABASE_USERNAME ?? 'postgres',
  password: process.env.DATABASE_PASSWORD ?? 'password',
  synchronize: false,
  logging: ['error'],
  autoLoadEntities: true,
  ssl: process.env.DATABASE_HOST !== undefined,
  extra: {
    // setting this to 0 to disable auto-disconnect cspell: disable-next-line
    idleTimeoutMillis: 60_000,
    keepAlive: true,
    keepAliveInitialDelayMillis: 60_000,
    max: 10,
    connectionTimeoutMillis: 30_000, // number of milliseconds to wait for connection
  },
};

We host this service on a Azure Kubernetes Service cluster, and are making connections to an Azure Database for PostgreSQL Flexible Server.

Recently, we upgraded our AKS Node SKUs from Standard_B4ms to Standard_D4as_v5, and started seeing a lot of the foll. error:

Error: Connection terminated due to connection timeout 
  at Client.<anonymous> (/usr/src/app/node_modules/pg-pool/index.js:251:17) 
  at Client.patchedClientConnectCallback (/usr/src/app/node_modules/@opentelemetry/instrumentation-pg/build/src/utils.js:309:12) 
  at /usr/src/app/node_modules/@opentelemetry/context-async-hooks/build/src/AbstractAsyncHooksContextManager.js:50:55 
  at AsyncLocalStorage.run (node:internal/async_local_storage/async_hooks:91:14) 
  at SentryContextManager.with (/usr/src/app/node_modules/@opentelemetry/context-async-hooks/build/src/AsyncLocalStorageContextManager.js:33:40) 
  at SentryContextManager.with (/usr/src/app/node_modules/@sentry/opentelemetry/build/cjs/index.js:1430:24) 
  at Client.contextWrapper [as _connectionCallback] (/usr/src/app/node_modules/@opentelemetry/context-async-hooks/build/src/AbstractAsyncHooksContextManager.js:50:32) 
  at Connection.<anonymous> (/usr/src/app/node_modules/pg/lib/client.js:145:18) 
  at Object.onceWrapper (node:events:632:28) 
  at Connection.emit (node:events:518:28) {   [cause]: Error: Connection terminated unexpectedly 
  at Connection.<anonymous> (/usr/src/app/node_modules/pg/lib/client.js:132:73) 
  at Object.onceWrapper (node:events:632:28) 
  at Connection.emit (node:events:518:28) 
  at Socket.<anonymous> (/usr/src/app/node_modules/pg/lib/connection.js:63:12) 
  at Socket.emit (node:events:518:28) 
  at TCP.<anonymous> (node:net:346:12) 
at TCP.callbackTrampoline (node:internal/async_hooks:130:17) } 

We reverted to using the Standard_B4ms SKU and the errors stopped. However, we do need to upgrade our SKUs. We did not have this error on our setup before this.

Any ideas what could be causing this error, and how we could fix this? The only possible explanation we could have found was that it could be related to Azure Accelerated Networking, but have no proof.