This topic describes how to manage cache disks in the Cloud Storage Gateway (CSG) console. For example, you can add a cache disk and increase cache disk capacity.
Prerequisites
An Internet Small Computer System Interface (iSCSI) gateway is created. For more information, see Create an iSCSI gateway.
Background information
Currently, iSCSI volumes support the Cache and Write Through modes. You can select a cache disk for each iSCSI volume that has the Cache mode enabled. The Cache mode allows read and write operations to use local cache disks first. If you need to create an iSCSI volume that has the Cache mode enabled, you must add a cache disk to the iSCSI gateway first.
Methods introduced in this topic apply only to cache disk management of iSCSI gateways deployed on Alibaba Cloud. If you want to add a cache disk for an on-premises iSCSI gateway, you must add a cache disk in the on-premises gateway console. For more information, see Add disks.
Add a cache disk
On the Gateways page, click the ID of the iSCSI gateway. On the page that appears, click .
Specify cache disk specifications by using Cache Calculator or Custom Cache settings.
Cache Calculator: Cache disk settings are automatically recommended based on your application requirements.
Custom Cache: You need to manually configure a cache disk type and capacity.
NoteCapacity
The supported capacity range of a cache disk varies with the gateway edition:
Basic: 20 GB to 4,096 GB
Standard: 20 GB to 8,192 GB
Enhanced or Performance Optimized: 20 GB to 3,2768 GB
Type
You can select Ultra Disk, Standard SSD, or ESSD. We recommend that you select ESSD.
If you add a cache disk to a subscription gateway, you are redirected to the cache disk purchase page. For more information, see Purchase a cache disk.
Increase cache disk capacity
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On the Caches tab, find the target cache disk and click the plus (+) icon.
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In the Scale Up Cache dialog box, set the cache size and click OK.
NoteWhen you increase the cache disk capacity, the limit on the new capacity varies with the edition of the gateway.
Basic: The new capacity must be greater than the current capacity and less than or equal to 4,096 GB.
Standard: The new capacity must be greater than the current capacity and less than or equal to 8,192 GB.
Enhanced or Performance Optimized: The new capacity must be greater than the current capacity and less than or equal to 32,768 GB.
If you use a subscription iSCSI gateway, after clicking OK, you are redirected to the payment page. On the payment page, change the size of the corresponding cache disk to the target size and complete the payment. The scaling operation starts automatically after payment is complete.
For example, to scale a 100 GB ESSD PL1 disk to 200 GB, change the ESSD (PL1) cache size to 200 GB on the payment page.