Elastic Compute Service:Usage notes

Operation notes

• After you create an ECS instance, only you have the administrator permissions on the instance and can log on to the instance.
• Do not resell or sublicense bandwidth assigned to your ECS instances without authorization. Failure to comply with the note causes your instances to be stopped, locked, and released.
• Do not use your ECS instances for malicious, fraudulent, or illegal activities, such as click farming or fraudulent transactions on e-commerce websites such as Taobao. Failure to comply with the note results in suspension or termination of your account.
• Do not uninstall relevant hardware drivers.
• Do not modify the media access control (MAC) addresses of network interface controllers (NICs) unless necessary.
• Do not enable SELinux.
• ECS instances with 4 GiB or larger memory must use 64-bit operating systems. A 32-bit operating system can address a maximum of 4 GiB of memory. Alibaba Cloud allows you to create instances that run the following 64-bit operating systems. The operating system versions on the instance buy page prevail.
  • Alibaba Cloud Linux 64-bit
  • CoreOS 64-bit
  • CentOS 64-bit
  • Debian 64-bit
  • FreeBSD 64-bit
  • openSUSE 64-bit
  • SUSE Linux 64-bit
  • Ubuntu 64-bit
  • Red Hat 64-bit
  • Windows 64-bit
• To ensure service continuity and prevent failover-induced service unavailability, we recommend that you configure relevant software to automatically start on instance startup. If service applications are connected to databases, we recommend that you enable auto-reconnection for these service applications.
• We recommend that you do not upgrade the kernel or operating system of an instance. To upgrade the kernel, see How do I prevent Linux instance startup failures after the kernel is upgraded?
• Specific software or application licenses must be bound to the hardware of ECS instances. After data is migrated from one instance to another, hardware information may change and invalidate the licenses.

Notes on Windows instances

• Do not stop the built-in AliyunService or shutdownmon.exe process. Otherwise, ECS instances may fail to be stopped or restarted in the ECS console.
• Do not modify the hostname of the domain controller.
• We recommend that you do not create custom images by using a virtual machine that acts as a domain controller.
• Do not rename, delete, or disable the administrator account. Otherwise, the use of the server may be affected.
• If your instance uses basic disks, we recommend that you do not use the virtual memory. If your instance uses ultra disks, standard SSDs, or enhanced SSDs (ESSDs), you can use the virtual memory.
• Proceed with caution when you use the administrator account to resize disks, manage spanned volumes or the registry, and update the system. Failure to comply with the note can result in data loss.
• A 32-bit Windows operating system supports up to four vCPUs.
• Make sure that a minimum of 2 GiB memory is available when you build a website or deploy a web environment on a Windows instance. Instance types that have only one vCPU and one GiB of memory do not support MySQL databases.
• For information about usage notes on images and operating systems, see Select an image.

Notes on Linux instances

• Do not modify the content of the default /etc/issue file on Linux instances. If you modify the /etc/issue file on a Linux instance and then use this instance to create a custom image, the operating system distribution of the image cannot be recognized. This causes instances created from the image to fail to start.
• Do not modify the permissions of the directories in the root partition, especially /etc, /sbin, /bin, /boot, /dev, /usr, and /lib. Improper modifications of permissions may cause errors.
• Do not rename, delete, or disable the root account.
• Do not compile the Linux kernel or perform operations on it.
• If your instance uses basic disks, we recommend that you do not use swap partitions. If your instance uses ultra disks, standard SSDs, or ESSDs, you can use swap partitions.
• Proceed with caution when you use the root account to run the fio, mkfs, or fsck command or resize disks. Failure to comply with the note can result in data loss.
• For information about usage notes on images and operating systems, see Select an image.

Limits

For information about limits on ECS, see Limits.