Advanced Backup Path Customization, ZSTD Compression, and Backup Management in DirectAdmin

1. Custom Append Path for Backup Locations

DirectAdmin allows administrators to customize backup paths using custom append values. This feature enables flexible retention strategies by dynamically generating folder names based on time formats.

1.1 Examples of Custom Append Path Usage

Daily Backups – No Append:

Backups overwrite daily, retaining only the most recent backup.

Daily Backups – Append: Weekday

Each backup is stored in a folder named after the weekday, creating a 7‑day retention cycle.

Weekly Backups – Append: Week Number

One backup per week, retaining 4 backups (one per week of the month).

Monthly Backups – Append: Month

One backup per month, retaining 12 backups per year.

Daily Backups – Append: Full Date

Retains all backups indefinitely. This may fill the disk unless combined with a cron job to delete older backups.

1.2 Using strftime for Custom Paths

The append path uses strftime formatting to generate folder names. Examples:

• %F → 2014‑03‑05
• %A → Wednesday
• %B → March
• %m/%d → 03/28

Allowed characters:

• a‑z
• A‑Z
• 0‑9
• % / - . _

Disallowed characters in the final path:

• :
• ,
• % (if produced in output)

Path generator tool:

http://strftime.net

1.3 Important Warning About Unsafe Paths

Dynamic paths must remain inside skipped backup directories to avoid recursive backups.

Safe example:

/home/admin/admin_backups/Wednesday

Unsafe example:

/home/admin/admin_backups_Wednesday

This may cause infinite recursive backups.

2. Enabling ZSTD Compression for Backups

DirectAdmin supports tar.zst compression, which is significantly faster and more efficient than gzip.

Enable ZSTD:

da config-set zstd 1
da config-set backup_gzip 2
systemctl restart directadmin

3. Which Folders Are Skipped During Backup?

To avoid loops and unnecessary data, DirectAdmin skips the following directories inside /home/USERNAME:

• backups
• user_backups
• admin_backups
• usr
• bin
• etc
• lib
• lib64
• tmp
• var
• sbin
• dev

3.1 Skipping Custom Paths

You can skip additional folders using:

Per‑User:

/usr/local/directadmin/data/users/USERNAME/skip_backup_home_files.list

Global:

/usr/local/directadmin/data/admin/skip_backup_home_files.list

Valid examples:

• Maildir
• application_backups

Invalid example:

• some/specific/path.txt

4. Adding a Date to Backup Filenames

To rename backups from:

user.admin.username.tar.gz

to:

user.admin.username.2024‑10‑15‑23‑32.tar.gz

Create this script:

#!/bin/sh
RESELLER=admin
BACKUP_PATH=`echo $file | cut -d/ -f1,2,3,4`
REQUIRED_PATH=/home/$RESELLER/admin_backups

if [ "$BACKUP_PATH" = "$REQUIRED_PATH" ]; then
   if [ "`echo $file | cut -d. -f4,5`" = "tar.gz" ]; then
       NEW_FILE=`echo $file | cut -d. -f1,2,3`.`date +%F-%H-%M`.tar.gz
       if [ -s "$file" ] && [ ! -e "$NEW_FILE" ]; then
           mv $file $NEW_FILE
       fi
   fi
fi
exit 0;

Make executable:

chmod 755 /usr/local/directadmin/scripts/custom/user_backup_success/dated_backup.sh

5. Moving Local Backups to an External Mount

If an external mount is writable only by root, DirectAdmin cannot write backups directly to it. The solution is to create backups locally and move them afterward.

Create this script:

#!/bin/bash
FROM=/home/admin/admin_backups
TO=/mnt/backups/
if [[ "${file}" == ${FROM}* ]]; then
    /bin/mv -f ${file} ${TO}
fi
exit 0;

Make executable:

chmod 755 /usr/local/directadmin/scripts/custom/user_backup_success/move_backups.sh

This script runs only when the backup completes successfully.