The Galera Manager¶
The Galera Manager is a graphical user interface for provisioning and monitoring Galera Clusters in various environments, like Amazon Web Services (AWS) or on-premises hardware. It allows an administrator to add nodes easily, and without having to configure each node, manually. Perhaps more useful is that Galera Manager provides charts for monitoring host and database metrics to ensure the proper and efficient functioning of a Galera Cluster. There are over a thousand metrics from which to choose. You may use any standard web browser for accessing Galera Manager, to administer and monitor clusters.
This section of the Codership documentation provides detailed information and instructions on how to install and configure Galera Manager. Below is a brief summary of each aspects of the process to start using Galera Manager, with each heading linked to the related page for much more information—there are also links in the margin to all pages of the Galera Manager documentation. However, if you’re an advanced administrator and are confident in your abilities, this page will provide you a summary of what you need to install and start using Galera Manager.
The Galera Manager Installer is provided to make installation and configuration of Galera Manager as simple as possible. This section is only a brief summary of the procedure. Some of this text contains links to other pages where you’ll find more detailed information on each step.
Choose or Create a Galera Manager Host
Galera Manager is a server program (it serves client requests from both the cluster nodes and graphical frontend) so it should be installed on a host (server or other computer) which can be connected to from both the prospective cluster nodes and a computer running the graphical client. A laptop behind a WiFi NAT is a poor choice. You may use a local computer (e.g., a desktop or laptop computer), but most administrators would want to use a computer in the same network as the cluster nodes. E.g. if the cluster is in EC2, you’d want to use an EC2 instance, if it is on premises, then you’d use a host in the on-premises network. It is also possible to use one of the cluster nodes, but it is recommended to have a dedicated Galera Manager Host.
At this point Galera Manager Installer supports the following x86_64 Linux distributions: Ubuntu 18.04 and 20.04, CentOS 7 and 8, Debian 10 (“buster”)
Future releases of Galera Manager Installer may support other platforms. For now, it’s recommended you use one of these distributions for Galera Manager Host. The Galera Manager itself will, however, manage or monitor clusters that may run on a different platform and nodes that will run either MySQL or MariaDB.
Download the Installer
After you’ve decided on and prepared the Galera Manager Host, you’ll need to download the Installer from Codership’s site at this address:
Run the Installer
Once the Installer has been downloaded, run it with superuser privileges to install Galera Manager. It will ask you some basic information: an administrative password, as well as a domain name and a site certificate, if you have these and want to use them.
chmod a+x gm-installer && sudo ./gm-installer installWhen the Installer is finished, the gmd daemon will be running on the Galera Manager Host. The Installer will print out some bookkeeping information that you may want to save for future reference and also the address at which you can connect to gmd from your browser and start using it:
INFO[0223] Galera Manager installation finished. Enter http://10.0.3.73 in a web browser to access.Check the Installing Galera Manager documentation page for more details on using the Installer and explanations of the questions you’ll be asked, as well as suggestions on how to respond to them. You might also read the Galera Manager Daemon (gmd) page.
Having installed Galera Manager, you’re now ready to use it to deploy a Galera cluster, including adding and configuring nodes.
Access Galera Manager
In the address field of your web browser, enter the address provided in the Installer output.
If you didn’t provide a certificate, your web browser may try to protect you from accessing the address. Push past those warnings until you reach the login screen. Then enter the administrative user name and password you gave when installing.
Create a Cluster & Add Nodes
After you log into Galera Manager, you may create a cluster, and then nodes to it. Typically, one would start with three nodes—you can add more nodes later, or delete some if you added too many. You will be able to choose between several node host types (
locallxd,unmanaged,ec2), host OS variants and database flavors. When you create a cluster, be sure to provide an public encryption key to facilitate manual troubleshooting via SSH connection.Log in to cluster
If you created a cluster from scratch, you’ll need to get the login credentials (i.e., user name, host address, password) to access one of the nodes with a MySQL client. This can be found by clicking on one of the nodes in Galera Manager, then its Configuration tab. There you’ll find the DB Address and the DB Root Password for accessing the database system.
You can find more details on deploying a cluster on the Deploying a Cluster in Galera Manager and the Adding Nodes with Galera Manager documentation pages. You may also find the Adding Users to Galera Manager page helpful at some point.
With a Galera Cluster and nodes in place, including the data loaded and accessible to users, you can monitor your cluster using charts of database and host metrics in Galera Manager. Still, you may want to configure these charts or add more to suit your particular needs.
Configure Charts
By default, there are a few charts configured for commonly watched metrics. However, there are over one-thousand metrics that you may track. Click on the cluster in Galera Manager and you’ll see the default charts. You may click the X at the top right of any chart to remove it. To add a chart, click the vertical ellipsis to access a pull-down menu where you can select Add Chart. A dialog box will appear for you to choose the metric you want to monitor.
For more information on adding charts and related information, see the Monitoring a Cluster with Galera Manager documentation page.
Galera Manager Documents
