Anti-ransomware backups temporarily cache data on your server to improve upload efficiency. If the cache grows too large — due to many large files or an interrupted backup process — backup jobs fail. Configure the hbr.config file to control the cache location and size limits.
The anti-ransomware client and Cloud Backup share the same client binary. Changes to the cache configuration affect both services. Assess the impact on Cloud Backup before making any changes.
How the backup cache works
During a backup, the anti-ransomware client writes two types of cache to the server:
Blob cache — stores data entry IDs and metadata from the backup source. Reduces network requests and speeds up subsequent backups.
File cache — stores file-level metadata for each backup path. A new file cache is created for each backup run.
Both caches are deleted from the server after the backup is uploaded to the cloud.
Excessive disk usage occurs in two situations: you have many large backup files, or a backup process fails to complete correctly.
Prerequisites
Before you begin, make sure you have:
Administrator access to the target server
Access to the Security Center console
Configure the backup cache
Step 1: Disable client self-protection
If client self-protection is enabled, disable it before modifying the configuration. Skipping this step may prevent the configuration file from taking effect.
Log on to the Security Center console. In the upper-left corner, select the region where your assets reside: Chinese Mainland or Outside Chinese Mainland.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.
In the left navigation pane, choose Assets > Host.
On the Host Asset page, find the target server and click View in the Actions column.
In the Defense Status section, turn off the Client Self-protection switch.
Step 2: Find the installation directory
Log on to the server with an administrator account and navigate to the anti-ransomware client installation directory.
| Client version | Operating system | Default installation directory |
|---|---|---|
| 1.X.X | Windows | C:\Program Files (x86)\Alibaba\Aegis\hbr\client |
| 1.X.X | Linux | /usr/local/aegis/hbr/client |
| 2.X.X | Windows | C:\Program Files (x86)\Alibaba\Aegis\hbrclient\client |
| 2.X.X | Linux | /usr/local/aegis/hbrclient/client |
To check your client version, go to Protection Configuration > Host Protection > Anti-ransomware in the Security Center console.
Step 3: Create and configure hbr.config
In the ../client directory (the installation directory), create a file named hbr.config.
Changes take effect immediately after you save the file. No server or virtual machine (VM) restart is required.
Settings apply only to subsequent backup jobs. Existing backup jobs are not affected.
The following example shows a complete hbr.config configuration:
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 = 2Blob cache parameters
Blob cache controls whether data entry IDs are cached in memory to accelerate backups.
| Parameter | Description | Default |
|---|---|---|
disable_blob_cache | Whether to disable data entry ID caching. Set to true to disable, false to enable. | false |
max_blob_cache_weight | Maximum system memory allocated to the blob cache, as a fraction of total memory. Must be between 0 and 1. | 0.15 (15%) |
cache_prefix | Absolute path where cached data entry IDs are stored. | — |
max_retain_count | Maximum number of cached data entry IDs to retain. | 16 |
File cache parameters
File cache stores file-level metadata for each backup path. These parameters apply to anti-ransomware client V2.13.1 and later.
| Parameter | Description | Default |
|---|---|---|
disable_file_cache | Whether to disable file metadata caching. Set to true to disable, false to enable. | false |
file_cache_max_size_hint | Maximum disk space for a single file cache. If exceeded, the backup fails with an "insufficient cache space" error. Increase this value if you back up a large number of files. | 32GB |
file_cache_disk_free_space_hint | Minimum free disk space required at the file cache location. If available space drops below this value, the backup fails. | 1GB |
file_cache_max_retain_count | Number of file caches retained per backup path. If set to 2, the caches from the last two backups are kept locally, so recovery is possible if the latest backup is deleted. | 2 |
Estimating disk space to reserve
Use the following formula to calculate how much disk space to reserve for file caches:
Space to reserve = 1.5 GB × (file_cache_max_retain_count + 1) + file_cache_disk_free_space_hintAs a reference: backing up 10 million files generates approximately 1.5 GB of cache per run. A new cache space is generated during each backup. The actual size depends on the number of source files, total data volume, and full path length.