What Is ZStack?
ZStack Cloud is an IaaS platform for private and hybrid clouds. It manages compute, storage, and network resources through APIs: workloads run as VM instances on compute nodes, volume data lives on primary storage, and images are stored on image storage servers.
Why ZStack Backup Matters?
Protection Against Accidental Deletion and Human Error
A VM deleted through the console cannot be recreated by the hypervisor, and a volume removed with it is gone. ZStack provides resource deletion protection to reduce the risk, but an independent copy on a backup server is what actually makes recovery possible.
Protection Against Host, Hardware, and Storage Failures
VM high availability restarts workloads on surviving hosts, which addresses availability rather than data protection. Primary storage holds the production copy of every volume, and distributed storage may replicate internally, but a logical error is replicated as faithfully as a correct write.
Protection Against Data Corruption
Most ZStack data corruption is logical rather than physical: a faulty update, a bad script, or a damaged application database. Because such changes reach every replica, protection depends on how many historical restore points exist and on how long they are retained.
Protection Against Ransomware and Cyberattacks
Ransomware targets production and backups alike. The practical defenses are copies that production credentials cannot modify, ideally on separate hardware or at another site, combined with strict access control on the backup server and verification that restored data is clean.
Business Continuity and Long-Term Retention Requirements
Business continuity depends on declared recovery objectives: backup determines how far back you can return, while the recovery environment determines how quickly workloads run again. Retention periods follow from business needs and from applicable regulation, not from a product default.
What Should You Back Up in a ZStack Environment?
ZStack Virtual Machines
VM instances are the center of most ZStack VM backup plans. Backup jobs protect VM instances with attached volumes included, and volumes can be protected individually. Shared volumes are not covered when a VM is backed up as a whole, so they need separate protection.
Business-Critical Applications Running on ZStack
Databases, ERP systems, file servers, web applications, and directory services behave differently under backup. Transactional workloads care about application consistency: a volume-level copy taken mid-transaction may restore to a logically inconsistent state even though the restore operation itself completes successfully.
ZStack Management and Configuration Information
Losing the management node database makes an environment hard to rebuild even when VM data survives. ZStack documents that database as a backup target; restoring it requires a global setting and restarts the management node. Configuration outside that scope needs separate records.
Backup Repositories and Backup Infrastructure
The backup destination needs protection too: hardware failure, deletion, unauthorized access, ransomware, and exhausted capacity all affect restores. ZStack's local backup server supports primary and standby roles with automatic switchover, and copies can be synchronized to a remote or public cloud server.
| Protection Target | Why It Matters | Protection Consideration |
| ZStack VMs | Protect business workloads | VM backup |
| Critical applications | Preserve application data | Application-consistent protection where required |
| ZStack configuration | Support infrastructure recovery | Configuration protection |
| Backup repository | Preserve recovery copies | Redundancy and security |
How to Design a ZStack Backup Strategy
Define RPO and RTO
Recovery Point Objective states how much data loss is acceptable and sets the interval between restore points; Recovery Time Objective states how long a workload may be unavailable and governs the recovery method. ZStack backup jobs support intervals down to 15 minutes, and CDP adds second-level recovery points.
Classify ZStack Workloads
Classify ZStack workloads by business impact before writing policies. Mission-critical VMs such as transaction databases and core ERP need the tightest RPO and RTO; business-critical systems such as mail and file servers tolerate daily or hourly copies; staging and sandbox workloads can be rebuilt.
Determine Backup Frequency
Frequency follows RPO. ZStack backup jobs can run as often as every 15 minutes, and a job supports network and disk QoS limits so that protection does not consume the production network during working hours, which matters when several jobs overlap.
Define Retention Policies
Retention within a ZStack backup strategy is a cost and compliance decision. ZStack retains local backup data by count or by age, and remote backup data permanently, by count, or by age. A daily, weekly, and monthly pattern covers short-term and long-term retention together.
Apply the 3-2-1 Backup Principle
The 3-2-1 principle maps onto ZStack: production volumes on primary storage, a copy on a local backup server, and a third copy on a remote or public cloud server. Copies that live only inside the environment they protect share its failure domain, so separation is the point.
Plan for Recovery
A strategy is incomplete until recovery is written down and rehearsed. ZStack's restore options differ by policy — restoring local backup data can create a new resource or overwrite the original — so the documented procedure must match the outcome the business expects.
How to Back Up ZStack
ZStack Native Backup Capabilities
ZStack's disaster recovery service contains the backup service module, which protects VM instances, volumes, and the management node database. It is licensed as a separate module on top of the platform license, and resources cannot be bound to jobs once the licensed quota is exhausted.
Jobs target local, remote, or public cloud backup servers, and can specify two local backup servers — the first primary, the second standby, with automatic switchover both ways — plus one remote backup server. After 63 increments the system runs a full backup, set by incrementalBackup.maxNum.
Snapshots are the other native mechanism, and ZStack adds CDP: continuous I/O capture with second-level recovery points, whole-VM and file-level recovery, and creation of a new VM instance from a recovery point without affecting the running original. CDP works with local, NFS, SharedBlock, and Ceph primary storage.
ZStack Snapshots vs. Backups
A snapshot is a point-in-time state kept close to production, while a backup is a restorable copy kept independently with its own retention. ZStack snapshot constraints matter: memory snapshots need a running VM, require external devices detached, pause the VM briefly, and are unsupported on Ceph primary storage.
| Aspect | Snapshot | Backup |
| Primary purpose | Short-term point-in-time state | Independent data protection |
| Dependency | Often closely tied to production infrastructure | Can be stored separately |
| Disaster protection | Limited depending on architecture | Better suited to independent recovery |
| Long-term retention | Generally not the primary purpose | Common backup use case |
| Ransomware resilience | Depends on implementation | Can use isolated/immutable repositories |
Third-Party ZStack Backup Solutions
Organizations that backup ZStack at scale often add a dedicated platform when native mechanisms fall short. Potential benefits include centralized management, automated policies, flexible retention, more recovery options, verification, disaster recovery, offsite protection, and cross-platform coverage; what a given ZStack backup software offers varies.
ZStack Backup and Recovery
Full VM Recovery
Full ZStack VM recovery rebuilds a VM instance from a backup. ZStack restores local backup data by overwriting the original resource or creating a new one, and the volume provisioning strategy can be set; since ZStack Cloud 5.0, restoring a VM backup also restores attached volume data.
File-Level Recovery
File-level recovery restores individual files instead of an entire VM. ZStack CDP supports it for Windows and Linux file systems and can preview files without restoring the system, covering images, PDF, and text files up to 10 MB, which shortens recovery for partial failures.
Point-in-Time Recovery
Point-in-time ZStack VM recovery depends on which restore points still exist. ZStack backup chains combine incremental and full backups, and CDP recovery points can be locked so that retention policies do not remove the point an investigation or audit depends on.
Recovery After Host or Storage Failure
When a host or storage system fails, recovery becomes a question of capacity and independent data. Because backup data resides on backup servers rather than the failed component's local paths, workloads can be restored to whatever compute and primary storage remains available.
Recovery After Ransomware
After a ransomware incident, the only acceptable restore point is one known to be clean. That requires isolated copies, restricted credentials, verification of the backup data itself, and a rehearsed recovery order starting with the identity and directory services everything depends on.
| Failure Scenario | Recovery Objective |
| Accidental VM deletion | Restore the affected VM |
| Data corruption | Recover a clean restore point |
| Host failure | Restore workload to available infrastructure |
| Storage failure | Recover from independent backup storage |
| Ransomware | Recover from a known-clean backup |
| Site disaster | Recover workloads at another location |
ZStack Backup Best Practices
Define RPO and RTO -- Set data-loss and downtime targets per workload class
Prioritize critical ZStack VMs -- Tier workloads, then bind them within the licensed quota
Automate backup jobs -- Use scheduled jobs, with QoS limits on busy networks
Use appropriate retention policies -- Local by count or age; remote permanent, by count, or by age
Maintain multiple backup copies -- Keep a local copy for fast restores plus an independent copy
Store copies outside the primary failure domain -- Synchronize to a remote or public cloud backup server
Protect backup repositories -- Restrict access, encrypt where supported, use primary/standby servers
Use application-consistent backup where required -- Confirm what consistency each method gives transactional workloads
Monitor backup jobs -- Enable failure alarms and review task records and capacity
Test recovery regularly -- Rehearse full VM, file-level, and database restores
Document recovery procedures -- Record restore policy, recovery order, owners, and escalation paths
Review backup capacity as ZStack grows -- Re-plan storage and licensed quota as VMs are added
Common ZStack Backup Mistakes
Treating Snapshots as the Only Backup
Risk: Snapshots stay with the production storage they capture, and ZStack disables snapshot groups when a shared volume is attached.
Practice: Treat snapshots as a rollback tool and keep an independent copy with its own retention, on storage production credentials cannot reach.
Keeping All Backup Copies in the Same Environment
Risk: A site failure or a compromised management node can take production and every local copy with it.
Practice:Synchronize copies to a remote or public cloud backup server so at least one copy sits outside the primary failure domain.
Applying the Same Backup Policy to Every VM
Risk: Uniform backup policies spend licensed capacity and backup storage on low-value workloads while under-protecting the workloads the business actually depends on.
Practice: Tier VMs by business impact, then assign the method, frequency, retention, and recovery path to each tier.
Ignoring Application Consistency and Recovery Testing
Risk: A volume-level copy of a busy database can restore to a state the application cannot start from, and a green backup job proves nothing about recoverability.
Practice: Confirm the consistency each method delivers, and rehearse restores including the database.
Neglecting Capacity, Monitoring, and Backup Security
Risk: Incremental chains and dependency data accumulate, silent job failures become permanent recovery gaps, and a backup server holding everything is a high-value target.
Practice: Size backup storage against retention, enable failure alarms, restrict access, and encrypt data where supported.
How Vinchin Protects ZStack Environments
Organizations that need centralized protection, flexible recovery, and broader disaster recovery capabilities may complement ZStack's native mechanisms with a dedicated backup platform. Vinchin Backup & Recovery provides data protection capabilities for ZStack environments.
ZStack VM Backup
Vinchin Backup & Recovery includes ZStack among the platforms it protects, covering ZStack VM backup, backup copy, archive, and fast data recovery for ZStack. Protection is built around the platform's VM instances, as it is with every other hypervisor the product supports.
Agentless Backup
Backups are agentless, so no agent is installed inside each ZStack VM, which removes per-VM agent lifecycle work. For ZStack Cloud environments with Ceph primary storage, Vinchin documents LAN-free data transfer over SAN to shorten backup windows and reduce load on the production network.
Flexible Backup and Recovery
Options include full backup, incremental backup, and forever incremental backup driven by Vinchin SpeedKit, a Changed Block Tracking alternative. Recovery options include full VM recovery, file-level recovery, and instant VM recovery; Vinchin states that a VM with key applications can be recovered in 15 seconds.
Centralized Management
Management is centralized in a single web console covering scheduling, policy management, monitoring, and reporting. For larger ZStack Cloud environments, backup nodes can be added so that backup jobs are processed separately by the main server and the added nodes.
Disaster Recovery
For disaster recovery, Vinchin provides offsite backup copies, which send independent copies of local backups to remote backup storage and cloud archives to public cloud storage, including AWS S3, Azure, and Wasabi. Those copies stay outside the primary failure domain.
Backup Security and Verification
Security capabilities documented for ZStack include data encryption, ransomware protection as an Enterprise edition feature, and backup verification. Vinchin's anti-ransomware mechanism is real-time I/O monitoring that blocks unauthorized modification of backups; it also supports malware scanning and WORM-based protection.
FAQ
Q1: What is the core difference between ZStack snapshot and backup?
A1: Snapshots are short-term point-in-time copies tied to primary storage, while backups create independent copies for disaster recovery and long-term retention.
Q2: Can ZStack native backup protect VM configuration alongside virtual disks?
A2: ZStack native backup mainly handles VM disk data. Extra manual export steps are required to save platform configuration separately.
Q3: What challenges exist when backing up ZStack virtual machines?
A3: Administrators need to handle snapshot I/O pressure, storage consumption, and ensure application consistency for database workloads. Vinchin Backup & Recovery simplifies this with agentless VM protection for ZStack.
Q4: Is application-consistent backup available for ZStack VMs?
A4: Yes. Application-consistent snapshots flush memory and pending writes. Vinchin Backup & Recovery supports application-consistent backup for Windows and Linux guest applications on ZStack VMs.
Q5: What RPO and RTO considerations should admins define for ZStack workloads?
A5: Classify VMs by business priority. Critical workloads need shorter RPO and faster RTO, while non-critical VMs can use longer backup intervals.
Conclusion
ZStack data protection starts with understanding the environment and naming its protection targets, then identifying critical workloads and defining RPO and RTO for each class. From there, build workload-appropriate policies, keep independent copies outside the primary failure domain, and protect the backup repositories themselves.
The remaining steps are operational: monitor every job, test recovery rather than trusting job status, document procedures, review capacity as the environment grows, and extend backup into disaster recovery. Organizations wanting centralized management, flexible recovery, and offsite protection for ZStack backup solutions can evaluate Vinchin Backup & Recovery or start a free trial.
