# Percona Monitoring and Management 2.26.0
Percona Monitoring and Management (PMM) is a free and open-source platform for managing and monitoring MySQL, MongoDB, and PostgreSQL performance.
## Release Highlights
- **Experimental Dashboards**
New experimental dashboards are introduced that will be shipped to the PMM users. These dashboards will be uploaded to the **Experimental** folder to enable the users to test them in their environment and provide feedback.
The following Dashboards are being shipped as part of this release:
- [K8s monitoring dashboard](https://www.percona.com/doc/percona-monitoring-and-management/2.x/details/dashboards/dashboard-cluster-summary.html)
- [Environment Overview dashboard](https://www.percona.com/doc/percona-monitoring-and-management/2.x/details/dashboards/dashboard-env-overview.html)
- [Environment Summary dashboard](https://www.percona.com/doc/percona-monitoring-and-management/2.x/details/dashboards/dashboard-environent-summary.html)
!!! caution alert alert-warning "Important"
These experimental dashboards are subject to change. It is recommended to use these dashboards for testing purposes only.
- **SMTP Configuration Verification**
When configuring an SMTP email server for sending out email notifications, you now have the option to test that your specified settings are correct.
The **Email** tab under **Configuration > Settings > Communication** now includes a **Test** button to send a test alert through the specified server.
For more information about setting up an SMTP email server, see [Configure](https://www.percona.com/doc/percona-monitoring-and-management/2.x/how-to/configure.html).
- **Breaking change for Integrated Alerting (Technical Preview)**
This release introduces major changes to the core structure of rule templates. As a result, alert rules and templates created in previous PMM versions are not compatible with PMM 2.26.0 and cannot be migrated to this new version. After upgrading, make sure to manually recreate any custom alert rules and rule templates that you want to transfer to PMM 2.26.0.
!!! caution alert alert-warning "Disclaimer"
Integrated Alerting is still a Preview functionality and, as such, subject to change. We recommend that early adopters use this feature for testing purposes only.
## New Features
* [PMM-9059](https://jira.percona.com/browse/PMM-9059): Following the recently introduced support for connecting PMM to Percona Platform, you now have the option to also unlink any servers that are no longer relevant to your Platform organization.
To disconnect a PMM server, go to **Configuration > Settings > Percona Platform** and click **Disconnect**.
You can check the list of servers connected to an organization in Percona Platform by clicking **View instances** on the Dashboard page. For more information, see [Configure](https://www.percona.com/doc/percona-monitoring-and-management/2.x/how-to/configure.html) for more details.
* [PMM-9312](https://jira.percona.com/browse/PMM-9312): Tech Preview Feature: PMM now captures the MongoDB metrics such as `dbStats`, `collStats`, `indexStats`, and `topmetrics`. See [Documentation](https://www.percona.com/doc/percona-monitoring-and-management/2.x/details/commands/pmm-admin.html) for more details.
## Improvements
* [PMM-9176](https://jira.percona.com/browse/PMM-9176): DBaaS - PMM now supports Percona Distribution for MongoDB Operator 1.10.0.
* [PMM-9159](https://jira.percona.com/browse/PMM-9159): DBaaS - PMM now supports Percona Kubernetes Operator for Percona XtraDB Cluster 1.10.0.
* [PMM-9180](https://jira.percona.com/browse/PMM-9180): Integrated Alerting > Add Alert Rule - Added the Template expression in a collapsible panel for an enhanced user experience (default view as collapsed) as the technical message could confuse the users.
* [PMM-7781](https://jira.percona.com/browse/PMM-7781): Integrated Alerting - Alert rules no longer depend on their source rule template after creation. This means that you can now update or delete rule templates without impacting existing rules that are based on that template. For more information, see [Integrated Alerting](../get-started/alerting.md).
* [PMM-9356](https://jira.percona.com/browse/PMM-9356): Added new experimental Environment dashboards in PMM.
* [PMM-9296](https://jira.percona.com/browse/PMM-9296): Disclaimer about Technical Preview feature added to Percona Platform - Connect PMM to Percona portal page.
## Bugs Fixed
* [PMM-9416](https://jira.percona.com/browse/PMM-9416): Upgrading to PMM 2.25.0 using docker (replacing the image) fails when upgrading from versions less than or equal to 2.23.0.
!!! caution alert alert-warning
It is recommended to upgrade directly to PMM 2.26.0 instead of 2.25.0 when updating from versions less than or equal to PMM 2.23.0 if your PMM doesn't have external access (access to `repo.percona.com`).
* [PMM-8867](https://jira.percona.com/browse/PMM-8867): Fixed an issue for PMM Client installation using the tarball script (without using RPMs) where the configuration was getting lost due to the configuration file `pmm-agent.yml` being recreated.
* [PMM-8094](https://jira.percona.com/browse/PMM-8094): DBaaS - Fixed an issue for paused clusters that froze with PSMDB v1.8 operators when all the pods were terminated, providing no cluster resumption option.
* [PMM-8535](https://jira.percona.com/browse/PMM-8535): DBaaS - Repeating error after force unregister
* [PMM-9144](https://jira.percona.com/browse/PMM-9144): Dashboard - Fixed the Add inventory page issue that indicated AWS RDS/Aurora supported only MySQL.
* [PMM-9289](https://jira.percona.com/browse/PMM-9289): **Get from Browser** on settings page does not fetch port in Public address field breaking the integration for Platform authentication.
* [PMM-9255](https://jira.percona.com/browse/PMM-9255): On connecting the PMM server to Percona Platform for an admin user insufficient access rights error message is thrown.
* [PMM-9049](https://jira.percona.com/browse/PMM-9049): Eliminated confusion around the current and available version date by adding a tooltip with an explanation for these dates.
* [PMM-9181](https://jira.percona.com/browse/PMM-9181): Integrated Alerting - Modified the label for the enable/disable button in order to avoid confusion.
* [PMM-5405](https://jira.percona.com/browse/PMM-5405): Fixed an issue where the `pmm-admin summary` command fails if a null value is passed for the `--filename` parameter.
* [PMM-8141](https://jira.percona.com/browse/PMM-8141): Fixed an issue where the metrics were not captured as the cleanup of the temporary folder on the client node deleted the requisite configuration file.