Disaster recovery planning in SCADA systems - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to specify the primary backup location in the disaster recovery plan.

SCADA systems

backup_location = "[1]"

Drag options to blanks, or click blank then click option'

A/etc/scada

B/var/data

C/mnt/backup_primary

D/tmp

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing temporary or system directories for backup location.

The primary backup location should be a dedicated and secure path like /mnt/backup_primary to ensure data safety.

2fill in blank

medium

Complete the command to create a snapshot of the SCADA system configuration for disaster recovery.

SCADA systems

scada_backup --create-snapshot [1]

Drag options to blanks, or click blank then click option'

A--full

B--incremental

C--dry-run

D--verbose

Attempts:

3 left

💡 Hint

Common Mistakes

Using incremental or dry-run options instead of full snapshot.

Using --full creates a complete snapshot, essential for disaster recovery.

3fill in blank

hard

Fix the error in the disaster recovery script to restore the SCADA system from backup.

SCADA systems

restore_scada --source [1] --force

Drag options to blanks, or click blank then click option'

A/home/user

B/backup/latest

C/var/log

D/etc/scada

Attempts:

3 left

💡 Hint

Common Mistakes

Using system config or log directories as restore source.

The restore source must point to the latest backup directory, such as /backup/latest.

4fill in blank

hard

Fill both blanks to configure the disaster recovery test schedule and notification email.

SCADA systems

test_schedule = "[1]"
notification_email = "[2]"

Drag options to blanks, or click blank then click option'

Aweekly

Bdaily

[e-mail]

[e-mail]

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing daily tests which may be too frequent.

Using support email instead of admin email.

Disaster recovery tests are often scheduled weekly and notifications sent to the [e-mail] email.

5fill in blank

hard

Fill all three blanks to define the recovery point objective, recovery time objective, and backup retention period.

SCADA systems

rpo = [1]
rto = [2]
retention_days = [3]

Drag options to blanks, or click blank then click option'

A15

B60

C7

D30

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing retention days with RPO or RTO values.

The recovery point objective (RPO) is often 15 minutes, recovery time objective (RTO) 60 minutes, and backup retention period 30 days.

Practice

1. What is the main purpose of disaster recovery planning in SCADA systems?

easy

A. To improve the system's daily performance

B. To add new features to the SCADA system

C. To prepare the system to recover quickly after an emergency

D. To reduce the cost of hardware components

Solution

1. Step 1: Understand disaster recovery planning

   Disaster recovery planning focuses on preparing for emergencies and restoring system operations quickly.

2. Step 2: Identify the main goal in SCADA context

   The goal is to recover the SCADA system fast after failures or disasters to avoid downtime.

3. Final Answer:

   To prepare the system to recover quickly after an emergency -> Option C

4. Quick Check:

   Disaster recovery = fast system recovery [OK]

Hint: Disaster recovery means quick system recovery after emergencies [OK]

Common Mistakes:

• Confusing disaster recovery with performance improvement
• Thinking it adds new features
• Assuming it reduces hardware costs

2. Which of the following is the correct syntax to schedule a daily backup using a cron job on a Linux SCADA server?

easy

A. 0 24 * * * /usr/local/bin/scada_backup.sh

B. 0 0 * * * /usr/local/bin/scada_backup.sh

C. * * 0 0 * /usr/local/bin/scada_backup.sh

D. 0 0 0 * * /usr/local/bin/scada_backup.sh

Solution

1. Step 1: Understand cron syntax for daily tasks

   The format is 'minute hour day month weekday'. For daily at midnight, use '0 0 * * *'.

2. Step 2: Match the correct cron expression

   0 0 * * * /usr/local/bin/scada_backup.sh uses '0 0 * * *' which means daily at 00:00 hours, running the backup script.

3. Final Answer:

   0 0 * * * /usr/local/bin/scada_backup.sh -> Option B

4. Quick Check:

   Daily midnight cron = 0 0 * * * [OK]

Hint: Cron daily at midnight is always '0 0 * * *' [OK]

Common Mistakes:

• Using invalid hour values like 24
• Mixing up the order of cron fields
• Using zero in wrong positions

3. Given this backup script snippet for SCADA data:

if [ -f /backup/scada_data.tar.gz ]; then
  rm /backup/scada_data.tar.gz
fi
tar -czf /backup/scada_data.tar.gz /var/scada/data

What will be the output or effect after running this script?

medium

A. The old backup file is deleted and a new compressed backup is created

B. The script will fail because of syntax errors

C. The backup file will be duplicated without deletion

D. Nothing happens because the script does not run any commands

Solution

1. Step 1: Analyze the script logic

   The script checks if the backup file exists, deletes it if yes, then creates a new compressed backup.

2. Step 2: Understand the commands' effect

   Removing the old file avoids duplication, and tar creates a new compressed archive of SCADA data.

3. Final Answer:

   The old backup file is deleted and a new compressed backup is created -> Option A

4. Quick Check:

   Old backup removed + new backup created = The old backup file is deleted and a new compressed backup is created [OK]

Hint: Check if file exists, remove it, then create new backup [OK]

Common Mistakes:

• Assuming the script duplicates backups
• Thinking the script has syntax errors
• Ignoring the file existence check

4. A SCADA disaster recovery plan script fails to restore data because the backup file path is incorrect. Which fix will solve this issue?

medium

A. Update the script to use the correct backup file path

B. Increase the server's CPU speed

C. Change the backup file format to .zip

D. Disable the firewall on the SCADA server

Solution

1. Step 1: Identify the cause of failure

   The script fails because it looks for a backup file in the wrong location.

2. Step 2: Apply the correct fix

   Changing the script to point to the correct backup file path will allow it to find and restore the data.

3. Final Answer:

   Update the script to use the correct backup file path -> Option A

4. Quick Check:

   Correct path fix = successful restore [OK]

Hint: Fix file path errors to restore backups correctly [OK]

Common Mistakes:

• Trying unrelated hardware fixes
• Changing file format without reason
• Disabling firewall unnecessarily

5. You need to design a disaster recovery plan for a SCADA system that ensures minimal downtime and data loss. Which combination of strategies is best?

hard

A. Relying solely on hardware redundancy without backups

B. Manual backups once a month and no testing

C. Only offsite storage without backups or testing

D. Regular automated backups, offsite storage, and periodic recovery drills

Solution

1. Step 1: Identify key disaster recovery needs

   Minimizing downtime and data loss requires frequent backups, safe storage, and testing the recovery process.

2. Step 2: Evaluate each strategy

   Regular automated backups, offsite storage, and periodic recovery drills combines automated backups (fast recovery), offsite storage (protection from local disasters), and drills (ensures plan works).

3. Final Answer:

   Regular automated backups, offsite storage, and periodic recovery drills -> Option D

4. Quick Check:

   Backup + offsite + testing = best recovery plan [OK]

Hint: Combine backups, offsite storage, and testing for best recovery [OK]

Common Mistakes:

• Skipping testing of recovery plans
• Relying only on hardware redundancy
• Doing backups too infrequently