Immutable Backup Best Practices for Modern Enterprises
How to make sure that malware or threat actors can’t change or delete backups
As ransomware attacks become more focused and damaging, old backup methods are no longer enough. Not only do modern attackers encrypt production data, they also look for backup systems and try to delete, corrupt, or encrypt them first. For businesses, this has made immutable backups a must-have for cyber resilience, not just a nice-to-have feature.
Immutable backups make sure that once data is written, it can’t be changed or deleted for a set amount of time. Even if attackers get administrative access, immutable data stays locked and can be recovered. To do immutability right, though, you need to do more than just turn on one feature. It needs careful design, control of who can access it, and regular checks.
Why regular backups aren’t enough anymore
Old backup models assume that attackers won’t be able to get to the backup infrastructure. That idea is no longer true. Before encrypting files, modern ransomware often turns off backup agents, deletes snapshot histories, and wipes replication targets.
Backups that privileged accounts can change, delete, or overwrite are always at risk. If malware gets into an administrator account, backups on systems that can be written to become just another target for attacks. Immutability gets rid of this risk by using technical controls that override both human and system-level privileges.
Basic Ideas Behind Immutable Backup Design
There are a few basic rules that all good immutable backup plans follow:
- WORM storage that keeps things from being changed after they are written
- Time-based retention locks that can’t be shortened
- Separate backup management from access to production
- Backup copies that are not connected to the internet or are logically separate
- Regular testing of recovery and verification
It is important to enforce immutability at the storage and snapshot levels, not just in backup software policies. This keeps you safe even if your backup software credentials are stolen.
How Synology protects backups that can’t be changed
Synology offers business-level immutability through a mix of immutable snapshots, WriteOnce shared folders, and strong access controls in DSM. These features let businesses lock backup data so that it can’t be deleted or changed, even by administrators, until the retention periods are over.
Immutable snapshots make recovery points that can’t be changed, which protects backup repositories from ransomware. WriteOnce shared folders are set up, they protect file-based backups as well, making sure that data cannot be changed once it has been written. Synology lets you layer immutability across local and secondary systems when you use snapshot replication and offsite targets together.
Full-volume encryption adds another layer of protection to backups that are not being used, making sure that even if someone steals them or gets access without permission, the data is still safe. When you add role-based access control and multi-factor authentication to backup systems, they become much harder to hack.
Best Ways to Use Immutable Backups
To get the most protection, businesses should follow these best practices:
1. Keep the backup infrastructure separate from the production
Backup systems should have their own credentials, separate networks, and limited access for administrators. Backup deletion or retention should not be automatically controlled by production administrators.
2. Make sure retention locks are in place
Retention periods should be set based on business and legal needs, and once they are set, they should not be able to be changed. Immutable retention stops attackers from making recovery windows shorter.
3. Make more than one copy that can’t be changed
Immutability should be present on several levels, like local NAS snapshots and offsite immutable cloud or secondary NAS replicas. This is in line with modern 3-2-1-1-0 backup plans.
4. Keep an eye on the integrity of the backup
Constant monitoring and alerting can help find failed backups, attempts to tamper with data, or strange access behavior. Backup storage is just as important as backup visibility.
5. Regularly test recovery
Immutable backups are only useful if you can quickly restore them. Scheduled recovery testing checks that both the data is safe and the system is ready to work in real-life situations.
Putting Immutability in line with Compliance and Cyber Insurance
To meet legal and regulatory standards, many industries now need data retention that can’t be changed. Immutable backups help healthcare, finance, education, and government environments meet compliance standards by making sure that data can be audited and is accurate.
Cyber insurance companies are also asking for proof of unchangeable backups more and more before they give out or renew policies. Businesses that adopt immutability lower their financial, operational, and reputational risk ahead of time.
A little bit about Epis Technology
Epis Technology helps businesses create and set up backup systems that can’t be changed on Synology platforms. Epis Technology is an expert in Synology consulting, setting up secure backups, protecting Microsoft 365 and Google Workspace, building large-scale storage systems, and planning for business continuity. Epis Technology makes sure that businesses can get clean data back even if they are hit by ransomware or an insider threat by using unchangeable snapshots, strong access controls, and tested recovery workflows.