Security Center:Solutions for when anti-ransomware backups occupy too much disk space

Problem description

Anti-ransomware backup jobs consume excessive disk space on the server.

Cause

Anti-ransomware backups temporarily use disk space. The cached data is deleted from the server after the backup is uploaded to the cloud. The cache can consume excessive disk space if you have many large backup files, or if a program does not run correctly.

Modify the backup cache configuration

Follow these steps to modify the cache location, status, and maximum memory usage.

1. If client self-protection is enabled for the server, disable it first.

   1. Log on to the Security Center console. In the upper-left corner of the console, select the region where your assets reside: Chinese MainlandChina or Outside Chinese Mainland.

   2. In the navigation pane on the left, choose Assets > Host.

   3. On the Host Asset page, find the target server and click View in the Actions column.

   4. In the Defense Status section, turn off the Client Self-protection switch.

      

2. Log on to the server with an administrator account.

3. Navigate to the installation path of the anti-ransomware client.

   The following table lists the default installation directory for different versions of the anti-ransomware client.

   Client version	Server operating system	Installation directory of the anti-ransomware client
   1.X.X	Windows	C:\Program Files (x86)\Alibaba\Aegis\hbr\client
   	Linux	/usr/local/aegis/hbr/client
   2.X.X	Windows	C:\Program Files (x86)\Alibaba\Aegis\hbrclient\client
   	Linux	/usr/local/aegis/hbrclient/client

4. In the installation directory of the anti-ransomware client, which is ../client by default, create an hbr.config file.

5. In the hbr.config file, add the following parameters to configure the data ID and metadata cache, and then save the file.

   Important

   • The parameter settings take effect immediately after you save the hbr.config file. You do not need to restart the server or VM.

   • The parameter settings are applied only to subsequent backup jobs. You cannot accelerate the existing backup jobs by caching data entry IDs and metadata.

   You can configure parameters in the hbr.config file to set the cache location, the maximum system memory usage for the cache, and other cache-related settings.

   The following example shows the configuration of the hbr.config file:

   disable_blob_cache = false
   max_blob_cache_weight = 0.15
   cache_prefix = D:\CacheFolder
   max_retain_count = 16 
   
   disable_file_cache = false
   file_cache_max_size_hint = 32GB  
   file_cache_disk_free_space_hint = 1GB
   file_cache_max_retain_count = 2

   Parameter	Description
   disable_blob_cache	Specifies whether to enable data ID caching. Caching data IDs and metadata from the backup source reduces network requests and accelerates backups. Valid values: true: Data ID caching is disabled. false: Data ID caching is enabled.
   max_blob_cache_weight	The maximum system memory that can be used by the cache for data entry IDs. Default value: 0.15. The value indicates 15% of the total system memory. The value must be between 0 and 1.
   cache_prefix	The path in which the cached data entry IDs are stored. The value must be an absolute path.
   max_retain_count	The maximum number of cached data entry IDs.
   disable_file_cache	Specifies whether to cache metadata. Valid values: true: does not cache metadata. false: caches metadata.
   file_cache_max_size_hint	The maximum disk space occupied by a file cache. Default value: 32 GB. If the disk space occupied by a file cache exceeds this value, the file backup fails and the system prompts that the file cache space is insufficient. In this case, set the file_cache_max_size_hint parameter to a larger value. For example, the backup cache of 10 million files occupies about 1.5 GB of disk space each time. The specific disk space occupied is related to the number of source files, the total data volume, and the full path length. A new cache space is generated during the backup. The formula to calculate the space to be reserved for the disk is: 1.5 GB × (file_cache_max_retain_count + 1) + file_cache_disk_free_space_hint. Note This parameter takes effect only for anti-ransomware client V2.13.1 and later.
   file_cache_disk_free_space_hint	The available space of the disk where a file cache is located. Default value: 1 GB. If the available disk space is less than this value, the file backup fails and the system prompts that the file cache space is insufficient. In this case, adjust the cache space as required. Note This parameter takes effect only for anti-ransomware client V2.13.1 and later.
   file_cache_max_retain_count	The number of file caches reserved for each backup path. Default value: 2. For example, if the value is set to 2, the caches of the last two backups are retained locally. If the latest backup is deleted, the second last backup can still be found. Note This parameter takes effect only for anti-ransomware client V2.13.1 and later.

   You can view the version of the anti-ransomware client on the Protection Configuration > Host Protection > Anti-ransomware page.