Backward Compatibility of Ice Versions

This page describes the guarantees and non-guarantees provided by Ice’s versioning scheme.

Major, Minor and Patch

An Ice release version has 3 components: major.minor.patch. For example, Ice 3.8.5.

A major release introduces a new major version, a minor release introduces a new minor version, and a patch release only introduces a new patch version.

Source-Code Compatibility

Ice keeps source code compatible across the patch releases of a minor version: code that builds with Ice 3.8.0 builds with Ice 3.8.5. Ice does not guarantee source-code compatibility between minor releases, such as 3.7 and 3.8.

The Upgrade Guide describes the significant API changes in this release that may impact source-code compatibility.

Binary Compatibility

Ice keeps binary compatibility across the patch releases of a minor version: an application built with Ice 3.8.0 runs with Ice 3.8.5. Ice does not guarantee binary compatibility between minor releases.

When upgrading to a new minor (or major) release, you always need to recompile your Slice files. You also need to upgrade your source code to use the latest Ice APIs.

On-the-Wire Compatibility

Ice maintains on-the-wire compatibility across releases: a client and a server using different Ice releases can communicate with each other.

Interface Compatibility

Ice and its services provide Slice interfaces that applications use, such as Ice::Locator, IceStorm::Topic or IceGrid::Query. Ice keeps these interfaces compatible across the patch releases of a minor version, but does not guarantee their compatibility between minor releases.

Changes to service interfaces can also make an administrative tool incompatible with a service from another minor release.

The Upgrade Guide describes interface changes made by Ice services.

Database Compatibility

The IceGrid and IceStorm services store data persistently in LMDB databases.

Ice keeps the database schema compatible across the patch releases of a minor version, but does not guarantee its compatibility between minor releases.

For example, you can start an IceGrid registry 3.8.5 using a database created by IceGrid registry 3.8.0. But there is no blanket guarantee that you can start IceGrid registry 3.9 using a database created by IceGrid registry 3.8.5.

The Upgrade Guide describes database schema changes made by IceGrid and IceStorm.