Upgrade Without Going Dark:
In-Service Software Upgrade
When you upgrade, decisions continue.
Volt In-Service Software Upgrade (ISSU) eliminates planned downtime. No maintenance windows. No service interruptions. No trade-off between staying current and staying operational.
Planned Downtime Is Still Downtime.
Security patches. Feature releases. Compliance updates. Traditional systems force you to schedule maintenance windows, notify customers, pause operations, and hope nothing breaks.
As a result, every upgrade becomes a liability instead of an improvement.
- Fraud controls pause
- Charging stops
- Payments queue
- SLAs are exposed
- Customers notice
The longer upgrades are delayed, the more risk accumulates. However, taking mission-critical systems offline isn’t acceptable either.
You shouldn’t have to choose between staying current and staying operational.
Continuous Decisioning, Even During Upgrades
ISSU allows Volt clusters to upgrade node-by-node while the system continues processing live traffic.
Zero-Downtime Rolling Upgrades
Nodes are upgraded individually while the cluster continues processing billions of events. Applications remain unaware.
No Extra Hardware Required
Upgrade in place. No temporary clusters. No expansion. No reduced redundancy during the upgrade window.
Coordinated Activation
New features activate only after all nodes complete their upgrade, ensuring consistent behavior across the entire system.
Maintained Redundancy
Multiple synchronized copies preserve full data protection throughout the process. No single point of failure is introduced.
Because upgrades happen in place, there is no service interruption, no data loss, and no degraded availability. The cluster evolves while remaining fully authoritative.
How Volt ISSU Works
No maintenance windows. No customer notifications.
No midnight change management calls.
Graceful Node Removal: A node is taken out of rotation. Because traffic redistributes automatically, no manual intervention is required.
Upgrade & Silent Rejoin: The upgraded node re-enters the cluster and synchronizes without manual intervention. As a result, the process is invisible to applications.
Cluster-Wide Consistency: New capabilities activate only when the entire cluster is aligned. This ensures no partially upgraded state is ever exposed.
Full Redundancy Maintained: K-safety remains intact throughout the upgrade cycle. Therefore, data protection is never compromised during the process.
What ISSU Enables
- Eliminate planned downtime entirely
- Protect revenue during upgrades
- Maintain five-nines availability
- Deploy security patches immediately
- Reduce operational complexity
- Upgrade as frequently as your business requires
Upgrades become invisible to users, and uneventful for operators.
Ready to eliminate downtime?
See how ISSU enables continuous software evolution, seamless upgrades, and zero service interruption, even under peak production load.
