Solace Event Broker Release Notes and LTS

Solace event broker release notes and support: the LTS and rolling release model, the 10.26.0 LTS supported to June 2028, and an upgrade practice.

Solace event broker release notes follow a model Solace adopted in June 2025: one long-term support (LTS) release each June, supported for two years with maintenance releases every two weeks, and rolling releases every two weeks in between that bring new features and are supported only until the next LTS (support dates). As of October 2026 the current LTS is 10.26.0, released on 23 June 2026 and supported to 23 June 2028. This page explains the model, the calendar, what 10.26.0 changed and how to plan upgrades for brokers that a plant or a business depends on.

It belongs to the Solace Platform overview in the Solace cluster.

How the Solace release model works

Solace’s support page defines three release types:

Type	What it is	Cadence	Supported for
LTS	A production-ready release	Each June	Two years
Maintenance	Security and product fixes for LTS releases only	Every two weeks	The life of its LTS
Rolling	A generally available release for new features and integration	Every two weeks after the LTS	Until the next LTS

Why it matters. Before June 2025 Solace also shipped “production” releases alongside LTS; 10.11.1, for example, was supported for about a year. The new model makes the choice binary: stay on an LTS and take fixes, or follow the rolling stream and take features. A broker on a rolling release must keep moving, because its support ends at the next LTS.

What gets backported. Fixes for severity 1 and 2 issues and vulnerabilities in LTS releases arrive through maintenance releases. Solace’s stated remediation targets are 15 days for critical vulnerabilities (CVSS 9.0 to 10.0), 30 days for high (7.0 to 8.9) and 90 days for medium and low.

Solace event broker release notes: the LTS calendar

Release	Type	Available	End of support
10.4.1	LTS (old model)	20 June 2023	15 June 2026 (ended)
10.8.1	LTS (old model)	14 June 2024	15 June 2027
10.11.1	Production (old model)	10 March 2025	15 March 2026 (ended)
10.25.0	LTS	25 June 2025	30 June 2027
10.26.0	LTS, current	23 June 2026	23 June 2028
10.27.0	LTS, planned	June 2027	June 2029

The current releases and dates come from Solace’s support dates page, as of October 2026. Broker firmware is called SolOS, and release compatibility is documented per version. The rolling stream after 10.26.0 is numbered 10.26.x; the exact latest rolling build is not stated on one public page, so check the download portal.

Each LTS overlaps the next by about a year. That year is the planning window: a broker on 10.25.0 has until 30 June 2027 to reach 10.26.0, which itself runs to June 2028.

What changed in 10.26.0

Solace’s 10.26.0 announcement describes it as consolidating a year of updates into one LTS baseline. Highlights:

Security: basic authentication can be disabled for SEMP and Broker Manager; a hybrid client identity chain falls back from local credentials to LDAP or Active Directory; encrypted debug packages are available to read-only roles.
Kubernetes: native readiness probes distinguish a broker that is alive from one that is ready, which matters during rolling upgrades.
Observability: appliances and self-managed software can export telemetry to Datadog, Dynatrace and Splunk; a show interface rates CLI command; distributed tracing for AMQP with W3C trace context.
Messaging: Dead Message Queue eligibility overrides at endpoint level, and 30 MB guaranteed messages on lower-scale software brokers for edge use.

Where to find Solace event broker release notes, and how to read them

Three places, three jobs. The support dates page is the calendar: what is supported and until when. The What’s New feed carries the narrative highlights of each LTS, such as the 10.26.0 post above. The documentation’s release compatibility pages are the engineering detail: per-version compatibility and the changes that affect an upgrade. Keep links to all three in the broker runbook.

Read release notes for behaviour, not features. A new feature you do not use costs nothing. A changed default can stop a plant. When reviewing a release, look first for:

Changed defaults in authentication, TLS or management access, such as the option in 10.26.0 to disable basic authentication for SEMP
Protocol behaviour, especially MQTT, where plant clients are least tolerant of change
Deprecations and removals that affect scripts, monitoring or Terraform
Upgrade path notes: which versions can upgrade directly to the target

An illustrative case. A plant runs a broker HA group on 10.25.0 and a cloud service at head office. With 10.25.0 support ending on 30 June 2027, the team plans the move to 10.26.0 for the spring shutdown, tests it against a copy of the plant’s MQTT and JMS clients in March, and schedules the cloud service upgrade for the same week through the self-serve window. Both ends of the mesh then sit on one LTS until June 2028.

LTS or rolling: choosing per broker

Question	LTS	Rolling
Behaviour stability	Fixes only, for two years	New features every two weeks
Upgrade effort	Once a year at most	Continuous until the next LTS
Best for	Production brokers serving operations	Development, test, early feature adoption
Risk	Waiting a year for a feature	Regressions from frequent change

Our default for a plant is LTS everywhere in production. A broker carrying production orders or quality results should change on a schedule the plant chooses, not every two weeks. Run a rolling release on a test broker if you need to evaluate a feature early.

An upgrade practice for Solace event brokers

Orange and blue sticky notes arranged in columns on a whiteboard planning board — Put the LTS calendar on the same board as shutdowns and maintenance windows. A broker upgrade is a planned change, not an IT chore.

Inventory versions. Record the SolOS version, form factor, edition and HA configuration of every broker, and the API versions of the applications that connect to them.
Map support dates onto your calendar. Mark each broker’s end of support and work back to an upgrade window, ideally a planned shutdown.
Read the release notes and compatibility pages for the target version, including API compatibility. Client APIs such as JCSMP carry their own version numbers.
Test in non-production with real topic hierarchies, queue configurations and client mixes, including MQTT clients from the plant.
Upgrade one node of an HA group at a time, following Solace’s documented procedure for that form factor. On Kubernetes, the 10.26.0 readiness probes support rolling upgrades.
Use the cloud upgrade window. Since August 2026 Solace Cloud customers can schedule their own broker upgrades.
Verify and record. Confirm message flow, DMR links and replication after the upgrade, and update the inventory.

Brokers on Kubernetes and OpenShift and HA and disaster recovery setups each have their own upgrade considerations. Where the broker is one of many plant systems ageing at once, the Solace architecture belongs in a wider modernization roadmap.

Where it gets hard

Rolling releases are a commitment. Their support ends at the next LTS, so a team that adopts rolling must keep upgrading.
The latest rolling build is hard to pin down. No single public page lists it; check the download portal.
APIs and brokers version separately. An application on an old API can block a broker upgrade, or the reverse.
HA and DR upgrades need sequencing. A primary, a backup, a monitoring node and a replication site are four steps, not one.
Older releases predate the model. 10.8.1 was released under the earlier scheme and is supported to June 2027; confirm what maintenance it still receives.

Frequently asked questions

What is the current Solace LTS release?

As of October 2026 the current long-term support release of Solace Event Broker is 10.26.0, made available on 23 June 2026 and supported until 23 June 2028. The previous LTS, 10.25.0, is supported until 30 June 2027, and the next, 10.27.0, is planned for June 2027 with support to June 2029. Check Solace's support dates page for changes.

How often does Solace release the event broker?

Since June 2025 Solace ships one long-term support release each June and rolling releases every two weeks after it. LTS releases receive maintenance releases with security and product fixes every two weeks for two years. Rolling releases introduce new features and are supported only until the next LTS release.

Should a plant run an LTS or a rolling release?

For production brokers that support operations, an LTS release is usually the right choice: it receives fixes for two years without new features changing behaviour underneath you. Rolling releases suit development and test brokers, or teams that need a specific new feature now and can upgrade every few weeks until the next LTS.

Where are the Solace event broker release notes?

Solace publishes the support calendar on its support dates page, feature highlights for each LTS on its What's New feed, and version compatibility and release notes in its documentation under Release Compatibility. Broker firmware is called SolOS. Client APIs such as JCSMP and the Python API have their own version numbers and notes.

Can Solace Cloud customers choose when brokers are upgraded?

Yes. In August 2026 Solace announced self-serve upgrades for event broker services in its cloud, letting customers schedule their own upgrade window. Self-managed software and appliance brokers have always been upgraded by their owners, following Solace's documented procedure for each form factor and high-availability configuration.

Solace Event Broker Release Notes: LTS, Rolling Releases and Upgrades