If you cannot connect to an Elastic Compute Service (ECS) instance by using Workbench or by using connection software, such as PuTTY, Xshell, and SecureCRT, you can connect to the instance by using Virtual Network Computing (VNC). Then, you can use the operational interface to view the real-time status of the instance.
Starting from July 10, 2023, you can securely connect to ECS instances by using VNC without specifying VNC logon passwords.
On July 10, 2023, Alibaba Cloud performed a security upgrade on VNC. Starting from July 10, 2023, Alibaba Cloud manages authentication credentials and performs end-to-end data encryption for VNC logons to instances. After the upgrade, you can enter instance usernames and passwords to log on to instances without specifying VNC logon passwords.
The logon password of the ECS instance to which you want to connect is set. If you have not set a password for the instance or if you have forgotten the password, you must reset the password for the instance. For more information, see Reset the logon password of an instance.
If you cannot connect to an ECS instance by using Workbench or connection software, you can connect to the instance by using VNC. Then, you can view the real-time status or issues of the instance operating system. The following table describes some operations that can be performed by using VNC after connecting to an instance and the corresponding scenarios.
Operation after an instance is connected by using VNC
The operating system of an instance may start slowly due to specific system checks.
Check the self-check progress.
The firewall of the instance operating system is enabled by mistake.
Disable the firewall.
The instance is intruded, which causes a high CPU utilization and high bandwidth usage.
Troubleshoot and terminate abnormal processes.
By default, a VNC connection session lasts for about 300 seconds. If you do not perform operations within the 300 seconds, the connection to the instance is automatically closed. You must reconnect to the instance.
Log on to the ECS console.
In the left-side navigation pane, choose .
In the upper-left corner of the top navigation bar, select a region.
On the Instances page, find the instance to which you want to connect and click Remote connection in the Actions column.
In the Remote connection dialog box, click Show Other Logon Methods. Then, click Sign in now in the VNC section.
Log on to the instance operating system.
Enter a username, such as root or ecs-user, and press the
Enter the logon password of the instance and press the
The characters of the password are hidden when you enter the password of the Linux instance.
You can switch between up to 10 different VNC management terminals when you connect to the Linux instance. The default terminal is CTRL+ALT+F1. For example, you can chooseto switch to CTRL+ALT+F2. A persistent black screen indicates that the instance is in sleep mode. Press a key to wake up the instance.
In the upper-left corner of the page that appears, choose.
Select an account, enter the logon password of the instance, and then press the Enter key.Note
The default account for Windows instances is Administrator.
Copy long commands
If you want to copy a long text such as a download URL from your computer to an instance, you can use the command copy feature.
Connect to the instance by using VNC.
In the upper-left corner of the page that appears, click Enter Copy Commands.
In the Copy and Paste Commands dialog box, enter the content to be copied and click OK.