Symptoms

• Symptom 1:
  • The upload speed is slow (below 8 Mbps) over a home network, while it is normal over a corporate network.
  • The upload speed is slow (below 8 Mbps) over a corporate network, while it is normal using a 4G network.
• Symptom 2: The upload is slow using a custom endpoint.

Possible Causes

• Symptom 1
  1. The speed slow due to your ISP and networking condition.
  2. CORS is used and thus the speed is slow.
• Symptom 2: CNAME maps the custom endpoint to other products (e.g., Content Delivery Network (CDN), Cloud Virtual Machine (CVM), or Anti-DDoS) before mapping to COS.

Solutions

• Symptom 1: Check the network condition of your client. For detailed directions, please see Troubleshooting Client-Side Network.
• Symptom 2: Reduce the intermediate links by modifying the DNS record for your custom endpoint to improve the transfer efficiency. For detailed directions, please see Modifying custom endpoint’s DNS record.

Troubleshooting Procedure

Checking the client-side network

1. Run the following command to check whether the IPS of the IP address is the same as that of the client:

   ping COS endpoint

   Example:

   ping examplebucket-1250000000.cos.ap-beijing.mqcloud.com

   • If yes, skip to Step 3.
   • If not, perform Step 2.

2. Check whether a proxy is enabled in the browser (Chrome is taken as an example).

   1. Open Chrome and click > Settings.

   2. Click Advanced. In the System area, click Open your computer’s proxy settings to open the configuration window of your OS.

      Check whether a proxy is enabled.

      • If yes, disable the proxy.
      • If not, perform Step 3.

3. Check whether your Wi-Fi router limits the speed.

   • If yes, allocate the bandwidth as needed.
   • If not, perform Step 4.

4. Test the performance of the upload to COS using the current network.
   The following example uses a 20 MB object and COS’s COSCMD to test the upload and download speeds:

   coscmd probe -n 1 -s 20

   A message similar to the following will be displayed, from which you can get the Average/Min/Max speeds:
   

5. Browse Speed Test to test the speed and compare the tested speed with data obtained in Step 4 to determine whether the client has used the maximum bandwidth.

   • If the speeds obtained in Step 4 are slower than the client bandwidth, please contact us.
   • If the speeds obtained in Step 4 equal to the client bandwidth but have not reached the speed promised by your ISP, please contact your ISP.
   • If the speeds obtained in Step 4 equal to the client bandwidth and reached the bandwidth promised by your ISP, please perform Step 6.

6. Check whether the client is accessing a bucket residing in a region in another country.

   • If yes, you are advised to enable COS’s Global Acceleration feature.
   • If not, please contact us.

Modifying DNS record for your custom endpoint

1. Check whether the custom endpoint is mapped to a COS endpoint.
   • If yes, please contact us.
     Common COS endpoints are as follows:

     XXX.cos.ap-beijing.myqcloud.com  (default COS endpoint)
     XXX.cos.accelerate.myqcloud.com (COS global acceleration endpoint)
     XXX.cos-website.ap-beijing.myqcloud.com (COS static website endpoint)
     XXX.picbj.myqcloud.com (COS’s default CI endpoint)

   • If not, perform Step 2.
     Common non-COS endpoints are as follows:

     XXX.file.myqcloud.com or XXX.cdn.dnsv1.com (Tencent Cloud’s CDN default endpoint)
     XXX.w.kunlungr.com (aliyunCDN default endpoint)

2. Map the custom endpoint to the desired COS endpoint in the CNAME and upload data.
   Example: upload.mydomain.com cname XXX.cos.ap-beijing.myqcloud.com. For detailed directions, please see Enabling Custom Accelerated Domain Name.
3. Modify the default COS endpoint of the client.
   The following uses C# as an example:

   CosXmlConfig config = new CosXmlConfig.Builder()
   .SetConnectionTimeoutMs(60000)  // Set the connection timeout in milliseconds. Defaults to 45000.
   .SetReadWriteTimeoutMs(40000)  // Set the read/write timeout period in milliseconds, which is 45,000 ms by default
   .IsHttps(true)  // Set HTTPS as default request method 
   .SetAppid(appid)  // Sets the APPID of your Tencent Cloud account
   .SetRegion(region)  // Sets the default bucket region
   .SetHost("XXXXXX.com") // Enter the custom endpoint.
   .SetDebugLog(true) .Build(); // Create the CosXmlConfig object.

   For more information about how to call other SDKs, please see SDK Overview.