This FAQ addresses common inquiries regarding the upgrade process for Consul. Designed to assist users with their upgrade endeavors, this KB article offers comprehensive answers to these frequently asked questions.
Q: What should be the exact sequence of upgrading Consul nodes?
You can upgrade consul by replacing the binary files and perform a rolling restart in the below given order.
Follower nodes -> Leader node > Client nodes
Q: What should I back up before upgrading Consul?
It is crucial to back up your Consul data directory before performing an upgrade. The data directory typically contains the Raft database, state snapshots, and other critical information. With a proper backup, you can revert to the previous version if any issues arise during the upgrade.
Reference: Backup Consul data and state | Consul | HashiCorp Developer
Q: What is the recommended upgrade path for Consul?
Consul maintains a support matrix that outlines the compatibility between different versions. It's generally recommended to follow a step-by-step upgrade path, moving from one supported version to the next. For example, if you are on Consul version 1.11.X, you may need to first upgrade to 1.12.X., then to 1.13.X, and so on until you reach the desired target version.
To know breaking changes and version based specific changes, please go through the link below.
Reference: https://github.com/hashicorp/consul/releases
For upgrade related steps and instructions, please go through the below reference link.
Reference: Upgrade Instructions | Consul | HashiCorp Developer
It is always recommended to follow the proper upgrade path to avoid large version jumps. Please go through the below links for the same.
Reference: Upgrading Specific Versions | Consul | HashiCorp Developer
Reference: Upgrade Consul | Consul | HashiCorp Developer
Q: Do I need to upgrade all agents?
It is not mandatory to upgrade all agents simultaneously, but it's advisable to do so to maintain consistency across the cluster. Consul is designed to handle mixed-version clusters during upgrades, but some new features may only be available when all agents are on the same version.
Q: Does upgrading Consul require changes to my configuration?
Upgrading Consul might require adjustments to your configuration files, as new versions may introduce changes or deprecate certain settings. Always review the release notes and documentation for changes that could impact your configuration.
To know breaking changes and version based specific changes, please go through the below link.
Reference: https://github.com/hashicorp/consul/releases
Q: Can I upgrade from any version of Consul directly to the latest version?
While Consul tries to maintain backward compatibility, it's generally recommended to follow the step-by-step upgrade path outlined in the documentation. Jumping multiple versions might lead to issues or compatibility problems. It is always recommended to follow the proper upgrade path to avoid large version jumps.
To know breaking changes and version based specific changes, please go through the below link.
Reference: https://github.com/hashicorp/consul/releases
Q: Are there any known issues or limitations with the new version of Consul?
Always check the release notes for any known issues, limitations, or breaking changes in the new version. This information can help you plan the upgrade and avoid potential problems. It is always recommended to cross check in your test environment first.
To know breaking changes and version based specific changes, please go through the below link.
Reference: https://github.com/hashicorp/consul/releases