Back up data on a local disk - Elastic Compute Service

To improve data security and prevent data loss or corruption caused by accidental deletion, modification, or overwriting, you can back up data that is stored on local disks on a regular basis. This topic describes three common backup methods: regular backup by using the Cloud Backup service, backup to Object Storage Service (OSS), and backup to cloud disks or File Storage NAS (NAS).

Method 1: Use Cloud Backup to back up data stored on a local disk on a regular basis

Scenario	Limit	Benefit	Billing
Cloud Backup provides features such as backup, data encryption, and rapid data restoration. Cloud Backup is suitable for scenarios that require highly reliable backup solutions. For more information about Cloud Backup, see Advantages of Cloud Backup?	Cloud Backup is not supported in specific regions. For information about the regions that support Cloud Backup, see Supported regions. Cloud Assistant Agent must be installed on the instance.	Convenient and efficient No need to compile scripts Support for incremental backup Support for backup and recovery	You are charged for file backup software usage and storage capacity. For information about the filling of the Elastic Compute Service (ECS) file backup feature, see the Billing section in the "Overview" topic.

Procedure

Make preparations.
- Make sure that Cloud Backup is supported in the region in which the local disk whose data you want to back up resides. For information about the regions that support Cloud Backup, see Supported regions.
- Make sure that Cloud Assistant Agent is installed on the instance equipped with the local disk.
  Important
  If the instance was purchased after December 1, 2017, Cloud Assistant Agent is provisioned on the instance. If Cloud Assistant Agent is not installed, you must install Cloud Assistant Agent on the instance. For more information, see Install Cloud Assistant Agent.
Log on to the Cloud Backup console and select the region in which the local disk resides.
In the left-side navigation pane, choose Backup > ECS File Backup. On the ECS Instances tab, find the instance equipped with the local disk and click Back Up in the Actions column.
On the Create Backup Plan panel, configure parameters as prompted and click OK.
Take note of the following configurations. For information about other parameters, see the Create a backup plan to periodically back up ECS files section in the "Back up files from an ECS instance" topic.
- Backup Folder Rule: Select Specified Folders.
- Source Paths: Enter the absolute data storage path of the local disk whose data you want to back up. You can enter multiple paths. For information about the rules, see the prompts.
- Backup Policy: Select a backup policy that specifies parameters such as the backup time, backup cycle, and backup retention period. If no backup policy appears, create a backup policy first. For more information, see the Create a backup policy section in the "Manage backup policies" topic.
When the backup time in the backup policy is reached, the system runs the backup job. If the Status of the backup job is Completed, the backup job is completed on the current day. You can view the historical backup points in the backup history.

Related operations

Restore data. After you back up data from a local disk to a cloud backup vault, you can restore files by using historical backup points if the files are missing or corrupted. For more information, see Restore files to an ECS instance.
Browse and download backup files. For more information, see the Browse and download backup files section in the "Back up files from an ECS instance" topic.

Method 2: Back up data from a local disk to OSS on a regular basis

You can run the ossutil and crontab commands and compile an automated script to back up data from a local disk to OSS on a regular basis.

Scenario	Requirement	Billing
This method is suitable for large-scale data backup scenarios, ideal for storage solutions that require low cost and high reliability. For more information about OSS, see Benefits.	Scripts must be compiled.	You are charged OSS storage fees. For more information, see Storage fees.

Important

This method provides a simple example on how to back up data from a local disk to OSS. You can optimize the example to meet your business requirements.

For example, full backup is performed each time, which causes incremental increases in storage space usage over time, or entire directories are packaged in ZIP files, which reduces backup speed and storage efficiency. In real business scenarios, you can use custom backup policies based on your business requirements. Examples:

Incremental or differential backups: Back up only the modified data since the previous backup to improve storage efficiency and accelerate the backup process.
Block backup: Before you back up data, you can divide the data set into multiple blocks or group the data based on logic such as the directory structure and file type.

Procedure

Make preparations.
- Activate OSS and create an OSS bucket. For more information, see Create a bucket.
- Obtain the OSS bucket name, OSS endpoint, and data storage path of the local disk whose data you want to back up.
Log on to the ECS instance.
Install the ossutil tool and configure the access credentials.
Important
To download the ossutil tool, make sure that the ECS instance equipped with the local disk has access to the Internet. For more information, see Enable public bandwidth for an ECS instance.
1. Install ossutil.
```
sudo yum install unzip -y
sudo -v ; curl https://gosspublic.alicdn.com/ossutil/install.sh | sudo bash
```
2. Configure the access credentials of ossutil.
  Create a .ossutilconfig file in the user directory and configure the credentials.
```
sudo -i # Switch to the root user. If the current user does not have sudo permissions, use other logon methods or grant the permissions.

cat <<EOF > /root/.ossutilconfig
[Credentials]
language=EN
endpoint=YourEndpoint
accessKeyID=YourAccessKeyId
accessKeySecret=YourAccessKeySecret
EOF
```
  Replace YourEndpoint, YourAccessKeyId, and YourAccessKeySecret with the actual values based on your business requirements.

Implement scheduled backup.

Install the compression tool. In this example, the zip tool is installed.
```
sudo yum install zip
```

Compile the backup script. In this example, the script is named backup_to_oss.sh.

The following code provides a sample script. You must modify the script based on your business requirements. The sample script is used to compress local disk data into a ZIP package and back up the ZIP package to the specified OSS bucket.

/path/to/your/local/data: Replace the value with the actual directory in which the local disk stores data.
your-bucket-name: Replace the value with the name of your OSS bucket.
path/in/oss/to/store/backups/: Replace the value with the directory in OSS in which you want to store the backup file.

#!/bin/bash

LOCAL_DIR="/path/to/your/local/data/"
BACKUP_TMP_DIR="/mnt/backup_tmp/"
OSS_BUCKET="your-bucket-name"
OSS_PREFIX="path/in/oss/to/store/backups/"
SYNC_TIME_FILE="/var/tmp/last_backup.timestamp"
OSSUTIL_PATH="/usr/bin/ossutil"
LOG_FILE="/var/log/backup_to_oss.log"
DATE_STAMP=$(date +%Y%m%d%H%M%S)
ZIP_FILE_NAME="backup_$DATE_STAMP.zip"

# Check whether the ZIP tool is installed.
if ! command -v zip &> /dev/null; then
    echo "zip command not found. Please install zip." >&2
    exit 1
fi

# Create a temporary backup directory if it does not exist.
mkdir -p "$BACKUP_TMP_DIR"

# Check whether LOCAL_DIR exists and is not empty.
if [ -z "$(ls -A "$LOCAL_DIR")" ]; then
    echo "No files to backup in $LOCAL_DIR" | tee -a "$LOG_FILE"
    exit 0
fi

# Package the files that you want to back up and capture error outputs.
(cd "$LOCAL_DIR" && zip -r "$BACKUP_TMP_DIR/$ZIP_FILE_NAME" .) >> "$LOG_FILE" 2>&1 || {
    echo "Failed to create ZIP archive. Error: $(zip -r "$BACKUP_TMP_DIR/$ZIP_FILE_NAME" . 2>&1)" | tee -a "$LOG_FILE"
    exit 1
}

if [ $? -eq 0 ]; then
    # Use ossutil to upload a ZIP file.
    OSS_PATH="oss://$OSS_BUCKET/$OSS_PREFIX$ZIP_FILE_NAME"
    if "$OSSUTIL_PATH" cp "$BACKUP_TMP_DIR/$ZIP_FILE_NAME" "$OSS_PATH" >> "$LOG_FILE" 2>&1; then
        echo "Uploaded: $ZIP_FILE_NAME" | tee -a "$LOG_FILE"
    else
        echo "Failed to upload: $ZIP_FILE_NAME" | tee -a "$LOG_FILE"
    fi
    rm "$BACKUP_TMP_DIR/$ZIP_FILE_NAME" # Delete the local ZIP file after a successful upload.
else
    echo "Failed to create ZIP archive." | tee -a "$LOG_FILE"
fi

# Record the backup time even if the backup fails to avoid re-uploading the same content.
date +%s > "$SYNC_TIME_FILE"
echo "Backup process completed." | tee -a "$LOG_FILE"

Grant the permissions to run the script and test the script.
```
sudo chmod +x /home/backup_to_oss.sh
./backup_to_oss.sh
```
Make sure that the script runs as expected and the data can be uploaded to OSS.
Run the crontab -e command to open the crontab editor and add a line to schedule your backup script. For example, run the following command to run the backup script at 02:00 every day:
```
0 2 * * * /home/backup_to_oss.sh
```
/home/backup_to_oss.sh: Replace the value with the actual storage path of the script.
You can configure other settings as needed.
- (Optional) Run the script on system startup.
  1. Create and open the backup_to_oss.service file.
    sudo vi /etc/systemd/system/backup_to_oss.service
  2. In the file, add the following content. Press the Esc key, enter :wq, and then press the Enter key to save and close the file.
    [Unit] Description=Back to OSS After=network.target [Service] ExecStart=/home/backup_to_oss.sh RestartSec=3 Restart=always [Install] WantedBy=default.target
  3. Run the following command to reload the systemd configuration:
    sudo systemctl daemon-reload
  4. Run the following commands to start the script and configure the script to start on system startup:
    sudo systemctl start backup_to_oss.service sudo systemctl enable backup_to_oss.service
- (Optional) Specify the retention period of backup files in OSS.
  1. Create an on-premises file and configure lifecycle rules in the XML format in the file.
    vim OSSLifecycleConfig.xml
    In the following example, a rule is configured to store the file in the test/ path of the bucket for 30 days, and all files stored longer than 30 days are deleted. You can modify the rule based on your business requirements. For more information, see the Create or modify lifecycle rules section in the "lifecycle" topic.
    <?xml version="1.0" encoding="UTF-8"?> <LifecycleConfiguration> <Rule> <ID>test-rule1</ID> <Prefix>test/</Prefix> <Status>Enabled</Status> <Expiration> <Days>30</Days> </Expiration> </Rule> </LifecycleConfiguration>
  2. ossutil reads and adds the lifecycle configurations to the specified bucket.
    ossutil lifecycle --method put oss://bucketname OSSLifecycleConfig.xml
    bucketname: Replace the value with the actual OSS bucket name.

Download backup data

You can download data that is backed up from OSS in the OSS console or by using ossutil. For more information, see Simple download.

Method 3: Back up data from a local disk to a cloud disk or NAS file system attached to the same instance on a regular basis

Periodically compress local disk data into a ZIP package and back up the data to a specific path of the cloud disk or NAS file system.

Scenario	Requirement	Billing
Cloud disk: suitable for scenarios in which online storage and easy access to backup files are required. NAS file system: suitable for data sharing and backup, or scenarios in which quick access to backup data is required.	Scripts must be compiled.	Backup to a cloud disk: You are charged for the cloud disk. For information about billing, see the Billing of cloud disks section of the "Block storage devices" topic. Backup to a NAS file system: NAS fees are generated. For information about billing, see Billing overview.

Important

This method provides a simple example on how to back up data from a local disk to OSS. You can optimize the example to meet your business requirements.

Incremental or differential backups: Back up only the modified data since the previous backup to improve storage efficiency and accelerate the backup process.
Block backup: Before you back up data, you can divide the data set into multiple blocks or group the data based on logic such as the directory structure and file type.

Procedure

Make preparations.
- Create a data disk for the instance equipped with the local disk, and attach and initialize the data disk. Alternatively, mount a NAS file system to the instance.
  For more information, see Quickly create and use a cloud disk or Step 2: Mount the file system in the NAS console of the "Mount a file system on a Linux ECS instance" topic.
- Obtain the mount path of the cloud disk or NAS file system, and the data storage path of the local disk whose data you want to back up.

Configure scheduled backup.

Log on to the ECS instance.
Install the ZIP tool. In the following example, Alibaba Cloud Linux is used.
```
sudo yum install zip
```

Compile the backup script. In this example, the script is stored in the /home/backup_script.sh directory.

Run the following command to compile and save the script:

vim /home/backup_script.sh

In the following example, a script is compiled to compress local disk data into a ZIP package and back up the ZIP package to a specific path. Modify the script based on your business requirements:

/path/to/local_disk/: Replace the value with the absolute data storage path of the local disk whose data you want to back up.
/path/to/backup/: Replace the value with the destination path of the data that you want to back up.

#!/bin/bash

# Configure variables.
LOCAL_DISK="/path/to/local_disk/"
NAS_MOUNT="/path/to/backup/"
ZIP_NAME="backup_$(date +%Y%m%d%H%M%S).zip"
LOG_FILE="/var/log/backup_to_nas.log"

# Make sure that the ZIP tool is installed.
if ! command -v zip &> /dev/null; then
    echo "Error: zip command not found. Please install zip." >&2
    exit 1
fi

# Back up data.
echo "Starting backup at $(date)" >> "$LOG_FILE"
zip -r "$NAS_MOUNT/$ZIP_NAME" "$LOCAL_DISK" >> "$LOG_FILE" 2>&1
if [ $? -eq 0 ]; then
    echo "Backup completed successfully at $(date)" | tee -a "$LOG_FILE"
    echo "Backup file: $NAS_MOUNT/$ZIP_NAME" | tee -a "$LOG_FILE"
else
    echo "Backup failed. Check log for details." >> "$LOG_FILE"
    exit 1
fi

# Clear expired backups. For example, retain the backups within the previous 30 days.

# find "$NAS_MOUNT" -type f -name 'backup_*' -mtime +30 -delete >> "$LOG_FILE" 2>&1
# if [ $? -eq 0 ]; then
#    echo "Old backups cleaned up successfully." >> "$LOG_FILE"
# else
#    echo "Error occurred while cleaning up old backups. Check log for details." >> "$LOG_FILE"
# fi

echo "Backup process finished at $(date)" >> "$LOG_FILE"

Save the script and grant the permissions to run the script.
```
sudo chmod +x /home/backup_script.sh
```
/home/backup_script.sh: Replace the value with the actual storage path of the script.
Run the crontab -e command to open the crontab editor and add a line to schedule your backup script. For example, run the following command at 02:00 every day:
```
0 2 * * * /home/backup_script.sh
```
/home/backup_script.sh: Replace the value with the actual storage path of the script.
(Optional) Run the script on system startup.
1. Create the backup_script.service file.
```
sudo vi /etc/systemd/system/backup_script.service
```
2. In the file, add the following content. Press the Esc key, enter :wq, and then press the Enter key to save and close the file.
```
[Unit]
Description=Backup Files Script
After=network.target

[Service]
ExecStart=/home/backup_script.sh

[Install]
WantedBy=default.target
```
3. Run the following command to reload the systemd configuration:
```
sudo systemctl daemon-reload
```
4. Run the following command to start the script and enable the cescript to start on system startup:
```
sudo systemctl start backup_script.service
sudo systemctl enable backup_script.service
```

Download backup data

Backup to a cloud disk: For more information, see Upload a file from on-premises to an ECS instance.
Backup to a NAS file system: For more information, see Migrate data from a NAS file system to an on-premises storage system.

Related operations

Migrate data from a local disk to another ECS instance
You can migrate all data of one or more instances with local disks to another ECS instance with a few clicks, and store the data in the cloud disks attached to the destination instance. This way, the data of the source instances with local disks is backed up. For more information, see Migrate servers to ECS instances.
Handle local disk damages
If a local disk is damaged, Alibaba Cloud triggers a system event and sends notifications, countermeasures, and event cycles. You can perform O&M based on scenarios. For more information, see O&M scenarios and system events for instances equipped with local disks.