Troubleshoot "Connection to XXXX refused" error in OSS Java SDK - Object Storage Service - Alibaba Cloud - Object Storage Service

Problem description

When you use the OSS Java software development kit (SDK), an error message similar to the following is returned.

Connection to http://buname.oss-cn-hangzhou-internal.aliyuncs.com refused
[RequestId]: Unknown
        at com.aliyun.oss.common.utils.ExceptionFactory.createNetworkException(ExceptionFactory.java:31)
        at com.aliyun.oss.common.comm.DefaultServiceClient.sendRequestCore(DefaultServiceClient.java:57)
        at com.aliyun.oss.common.comm.ServiceClient.sendRequestImpl(ServiceClient.java:191)
        at com.aliyun.oss.common.comm.ServiceClient.sendRequest(ServiceClient.java:151)
        at com.aliyun.oss.internal.OSSOperation.send(OSSOperation.java:71)
        at com.aliyun.oss.internal.OSSObjectOperation.putObject(OSSObjectOperation.java:92)
        at com.aliyun.oss.OSSClient.putObject(OSSClient.java:394)
        at osscs1.OSSPutObjectSample.uploadFile(OSSPutObjectSample.java:82)
        at osscs1.OSSPutObjectSample.main(OSSPutObjectSample.java:46)

Problem causes

The client and OSS are not in the private network of the same region. Therefore, the public endpoint must be used instead of the internal endpoint.
Even if the client and OSS are in the same region, the client may have restrictions, such as closed ports.

Solution

On the client, use the `ping` command to test the public endpoint. Use the `telnet` command to test if ports 80 and 443 are open. If these tests pass, configure the OSS Java SDK as follows.

private static final String OSS_ENDPOINT = "http://oss-cn-hangzhou.aliyuncs.com/";
OSSClient client = new OSSClient(OSS_ENDPOINT,ACCESS_ID, ACCESS_KEY);

Note

This topic uses the Hangzhou region and the http://oss-cn-hangzhou.aliyuncs.com/ endpoint as an example. For other regions, change the endpoint accordingly. For more information, see Endpoints and data centers.

Applies to

Object Storage Service (OSS)