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Reconfigure PerconaXtraDB Cluster Database
This guide will show you how to use KubeDB
Enterprise operator to reconfigure a PerconaXtraDB Cluster.
Before You Begin
At first, you need to have a Kubernetes cluster, and the
kubectl
command-line tool must be configured to communicate with your cluster.Install
KubeDB
Community and Enterprise operator in your cluster following the steps here.You should be familiar with the following
KubeDB
concepts:
To keep everything isolated, we are going to use a separate namespace called demo
throughout this tutorial.
$ kubectl create ns demo
namespace/demo created
Now, we are going to deploy a PerconaXtraDB
Cluster using a supported version by KubeDB
operator. Then we are going to apply PerconaXtraDBOpsRequest
to reconfigure its configuration.
Prepare PerconaXtraDB Cluster
Now, we are going to deploy a PerconaXtraDB
Cluster database with version 10.6.16
.
Deploy PerconaXtraDB
At first, we will create px-config.cnf
file containing required configuration settings.
$ cat px-config.cnf
[mysqld]
max_connections = 200
read_buffer_size = 1048576
Here, max_connections
is set to 200
, whereas the default value is 151
. Likewise, read_buffer_size
has the deafult value 131072
.
Now, we will create a secret with this configuration file.
$ kubectl create secret generic -n demo px-configuration --from-file=./px-config.cnf
secret/px-configuration created
In this section, we are going to create a PerconaXtraDB object specifying spec.configSecret
field to apply this custom configuration. Below is the YAML of the PerconaXtraDB
CR that we are going to create,
apiVersion: kubedb.com/v1
kind: PerconaXtraDB
metadata:
name: sample-pxc
namespace: demo
spec:
version: "8.0.26"
replicas: 3
configSecret:
name: px-configuration
storageType: Durable
storage:
storageClassName: "standard"
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 1Gi
deletionPolicy: WipeOut
Let’s create the PerconaXtraDB
CR we have shown above,
$ kubectl create -f https://github.com/kubedb/docs/raw/v2024.11.18/docs/guides/percona-xtradb/reconfigure/cluster/examples/sample-pxc-config.yaml
perconaxtradb.kubedb.com/sample-pxc created
Now, wait until sample-pxc
has status Ready
. i.e,
$ kubectl get perconaxtradb -n demo
NAME VERSION STATUS AGE
sample-pxc 8.0.26 Ready 71s
Now, we will check if the database has started with the custom configuration we have provided.
First we need to get the username and password to connect to a perconaxtradb instance,
$ kubectl get secrets -n demo sample-pxc-auth -o jsonpath='{.data.\username}' | base64 -d
root
$ kubectl get secrets -n demo sample-pxc-auth -o jsonpath='{.data.\password}' | base64 -d
nrKuxni0wDSMrgwy
Now, we will check if the database has started with the custom configuration we have provided.
$ kubectl exec -it -n demo sample-pxc-0 -- bash
Defaulted container "perconaxtradb" out of: perconaxtradb, px-coordinator, px-init (init)
bash-4.4$ mysql -u${MYSQL_ROOT_USERNAME} -p${MYSQL_ROOT_PASSWORD}
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 3699
Server version: 8.0.26-16.1 Percona XtraDB Cluster (GPL), Release rel16, Revision b141904, WSREP version 26.4.3
Copyright (c) 2009-2021 Percona LLC and/or its affiliates
Copyright (c) 2000, 2021, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> show variables like 'max_connections';
+-----------------+-------+
| Variable_name | Value |
+-----------------+-------+
| max_connections | 200 |
+-----------------+-------+
1 row in set (0.00 sec)
# value of `read_buffer_size` is same as provided
mysql> show variables like 'read_buffer_size';
+------------------+--------+
| Variable_name | Value |
+------------------+--------+
| read_buffer_size | 1048576 |
+------------------+--------+
1 row in set (0.00 sec)
mysql> exit
Bye
As we can see from the configuration of ready perconaxtradb, the value of max_connections
has been set to 200
and read_buffer_size
has been set to 1048576
.
Reconfigure using new config secret
Now we will reconfigure this database to set max_connections
to 250
and read_buffer_size
to 122880
.
Now, we will create new file new-px-config.cnf
containing required configuration settings.
$ cat new-px-config.cnf
[mysqld]
max_connections = 250
read_buffer_size = 122880
Then, we will create a new secret with this configuration file.
$ kubectl create secret generic -n demo new-px-configuration --from-file=./new-px-config.cnf
secret/new-px-configuration created
Create PerconaXtraDBOpsRequest
Now, we will use this secret to replace the previous secret using a PerconaXtraDBOpsRequest
CR. The PerconaXtraDBOpsRequest
yaml is given below,
apiVersion: ops.kubedb.com/v1alpha1
kind: PerconaXtraDBOpsRequest
metadata:
name: pxops-reconfigure-config
namespace: demo
spec:
type: Reconfigure
databaseRef:
name: sample-pxc
configuration:
configSecret:
name: new-px-configuration
Here,
spec.databaseRef.name
specifies that we are reconfiguringsample-pxc
database.spec.type
specifies that we are performingReconfigure
on our database.spec.configuration.configSecret.name
specifies the name of the new secret.
Let’s create the PerconaXtraDBOpsRequest
CR we have shown above,
$ kubectl apply -f https://github.com/kubedb/docs/raw/v2024.11.18/docs/guides/percona-xtradb/reconfigure/cluster/examples/reconfigure-using-secret.yaml
perconaxtradbopsrequest.ops.kubedb.com/pxops-reconfigure-config created
Verify the new configuration is working
If everything goes well, KubeDB
Enterprise operator will update the configSecret
of PerconaXtraDB
object.
Let’s wait for PerconaXtraDBOpsRequest
to be Successful
. Run the following command to watch PerconaXtraDBOpsRequest
CR,
$ kubectl get perconaxtradbopsrequest --all-namespaces
NAMESPACE NAME TYPE STATUS AGE
demo pxops-reconfigure-config Reconfigure Successful 3m8s
We can see from the above output that the PerconaXtraDBOpsRequest
has succeeded. If we describe the PerconaXtraDBOpsRequest
we will get an overview of the steps that were followed to reconfigure the database.
$ kubectl describe perconaxtradbopsrequest -n demo pxops-reconfigure-config
Name: pxops-reconfigure-config
Namespace: demo
Labels: <none>
Annotations: <none>
API Version: ops.kubedb.com/v1alpha1
Kind: PerconaXtraDBOpsRequest
Metadata:
Creation Timestamp: 2022-06-10T04:43:50Z
Generation: 1
Resource Version: 1123451
UID: 27a73fc6-1d25-4019-8975-f7d4daf782b7
Spec:
Configuration:
Config Secret:
Name: new-px-configuration
Database Ref:
Name: sample-pxc
Type: Reconfigure
Status:
Conditions:
Last Transition Time: 2022-06-10T04:43:50Z
Message: Controller has started to Progress the PerconaXtraDBOpsRequest: demo/pxops-reconfigure-config
Observed Generation: 1
Reason: OpsRequestProgressingStarted
Status: True
Type: Progressing
Last Transition Time: 2022-06-10T04:47:25Z
Message: Successfully restarted PerconaXtraDB pods for PerconaXtraDBOpsRequest: demo/pxops-reconfigure-config
Observed Generation: 1
Reason: SuccessfullyRestatedPetSet
Status: True
Type: RestartPetSetPods
Last Transition Time: 2022-06-10T04:47:30Z
Message: Successfully reconfigured PerconaXtraDB for PerconaXtraDBOpsRequest: demo/pxops-reconfigure-config
Observed Generation: 1
Reason: SuccessfullyDBReconfigured
Status: True
Type: DBReady
Last Transition Time: 2022-06-10T04:47:30Z
Message: Controller has successfully reconfigure the PerconaXtraDB demo/pxops-reconfigure-config
Observed Generation: 1
Reason: OpsRequestProcessedSuccessfully
Status: True
Type: Successful
Observed Generation: 3
Phase: Successful
Now let’s connect to a perconaxtradb instance and run a perconaxtradb internal command to check the new configuration we have provided.
$ kubectl exec -it -n demo sample-pxc-0 -- bash
Defaulted container "perconaxtradb" out of: perconaxtradb, px-coordinator, px-init (init)
bash-4.4$ mysql -u${MYSQL_ROOT_USERNAME} -p${MYSQL_ROOT_PASSWORD}
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 3699
Server version: 8.0.26-16.1 Percona XtraDB Cluster (GPL), Release rel16, Revision b141904, WSREP version 26.4.3
Copyright (c) 2009-2021 Percona LLC and/or its affiliates
Copyright (c) 2000, 2021, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> show variables like 'max_connections';
+-----------------+-------+
| Variable_name | Value |
+-----------------+-------+
| max_connections | 250 |
+-----------------+-------+
1 row in set (0.00 sec)
# value of `read_buffer_size` is same as provided
mysql> show variables like 'read_buffer_size';
+------------------+--------+
| Variable_name | Value |
+------------------+--------+
| read_buffer_size | 122880 |
+------------------+--------+
1 row in set (0.00 sec)
mysql> exit
Bye
As we can see from the configuration has changed, the value of max_connections
has been changed from 200
to 250
and and the read_buffer_size
has been changed 1048576
to 122880
. So the reconfiguration of the database is successful.
Reconfigure Existing Config Secret
Now, we will create a new PerconaXtraDBOpsRequest
to reconfigure our existing secret new-px-configuration
by modifying our new-px-config.cnf
file using applyConfig
. The PerconaXtraDBOpsRequest
yaml is given below,
apiVersion: ops.kubedb.com/v1alpha1
kind: PerconaXtraDBOpsRequest
metadata:
name: pxops-reconfigure-apply-config
namespace: demo
spec:
type: Reconfigure
databaseRef:
name: sample-pxc
configuration:
applyConfig:
new-px-config.cnf: |
[mysqld]
max_connections = 230
read_buffer_size = 1064960
innodb-config.cnf: |
[mysqld]
innodb_log_buffer_size = 17408000
Note: You can modify multiple fields of your current configuration using
applyConfig
. If you don’t have any secrets thenapplyConfig
will create a secret for you. Here, we modified value of our two existing fields which aremax_connections
andread_buffer_size
also, we modified a new fieldinnodb_log_buffer_size
of our configuration.
Here,
spec.databaseRef.name
specifies that we are reconfiguringsample-pxc
database.spec.type
specifies that we are performingReconfigure
on our database.spec.configuration.applyConfig
contains the configuration of existing or newly created secret.
Before applying this yaml we are going to check the existing value of our new field,
$ kubectl exec -it -n demo sample-pxc-0 -- bash
Defaulted container "perconaxtradb" out of: perconaxtradb, px-coordinator, px-init (init)
bash-4.4$ mysql -u${MYSQL_ROOT_USERNAME} -p${MYSQL_ROOT_PASSWORD}
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 3699
Server version: 8.0.26-16.1 Percona XtraDB Cluster (GPL), Release rel16, Revision b141904, WSREP version 26.4.3
Copyright (c) 2009-2021 Percona LLC and/or its affiliates
Copyright (c) 2000, 2021, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> show variables like 'innodb_log_buffer_size';
+------------------------+----------+
| Variable_name | Value |
+------------------------+----------+
| innodb_log_buffer_size | 16777216 |
+------------------------+----------+
1 row in set (0.00 sec)
PerconaXtraDB [(none)]> exit
Bye
16777216
Here, we can see the default value for innodb_log_buffer_size
is 16777216
.
Let’s create the PerconaXtraDBOpsRequest
CR we have shown above,
$ kubectl apply -f https://github.com/kubedb/docs/raw/v2024.11.18/docs/guides/percona-xtradb/reconfigure/cluster/examples/pxops-reconfigure-apply-config.yaml
perconaxtradbopsrequest.ops.kubedb.com/pxops-reconfigure-apply-config created
Verify the new configuration is working
If everything goes well, KubeDB
Enterprise operator will update the configSecret
of PerconaXtraDB
object.
Let’s wait for PerconaXtraDBOpsRequest
to be Successful
. Run the following command to watch PerconaXtraDBOpsRequest
CR,
$ kubectl get perconaxtradbopsrequest pxops-reconfigure-apply-config -n demo
NAME TYPE STATUS AGE
pxops-reconfigure-apply-config Reconfigure Successful 4m59s
We can see from the above output that the PerconaXtraDBOpsRequest
has succeeded. If we describe the PerconaXtraDBOpsRequest
we will get an overview of the steps that were followed to reconfigure the database.
$ kubectl describe perconaxtradbopsrequest -n demo pxops-reconfigure-apply-config
Name: pxops-reconfigure-apply-config
Namespace: demo
Labels: <none>
Annotations: <none>
API Version: ops.kubedb.com/v1alpha1
Kind: PerconaXtraDBOpsRequest
Metadata:
Creation Timestamp: 2022-06-10T09:13:49Z
Generation: 1
Resource Version: 14120
UID: eb8d5df5-a0ce-4011-890c-c18c0200b5ac
Spec:
Configuration:
Apply Config:
innodb-config.cnf: [mysqld]
innodb_log_buffer_size = 17408000
new-px-config.cnf: [mysqld]
max_connections = 230
read_buffer_size = 1064960
Database Ref:
Name: sample-pxc
Type: Reconfigure
Status:
Conditions:
Last Transition Time: 2022-06-10T09:13:49Z
Message: Controller has started to Progress the PerconaXtraDBOpsRequest: demo/pxops-reconfigure-apply-config
Observed Generation: 1
Reason: OpsRequestProgressingStarted
Status: True
Type: Progressing
Last Transition Time: 2022-06-10T09:13:49Z
Message: Successfully prepared user provided custom config secret
Observed Generation: 1
Reason: PrepareSecureCustomConfig
Status: True
Type: PrepareCustomConfig
Last Transition Time: 2022-06-10T09:17:24Z
Message: Successfully restarted PerconaXtraDB pods for PerconaXtraDBOpsRequest: demo/pxops-reconfigure-apply-config
Observed Generation: 1
Reason: SuccessfullyRestatedPetSet
Status: True
Type: RestartPetSetPods
Last Transition Time: 2022-06-10T09:17:29Z
Message: Successfully reconfigured PerconaXtraDB for PerconaXtraDBOpsRequest: demo/pxops-reconfigure-apply-config
Observed Generation: 1
Reason: SuccessfullyDBReconfigured
Status: True
Type: DBReady
Last Transition Time: 2022-06-10T09:17:29Z
Message: Controller has successfully reconfigure the PerconaXtraDB demo/pxops-reconfigure-apply-config
Observed Generation: 1
Reason: OpsRequestProcessedSuccessfully
Status: True
Type: Successful
Observed Generation: 3
Phase: Successful
Now let’s connect to a perconaxtradb instance and run a perconaxtradb internal command to check the new configuration we have provided.
$ kubectl exec -it -n demo sample-pxc-0 -- bash
Defaulted container "perconaxtradb" out of: perconaxtradb, px-coordinator, px-init (init)
bash-4.4$ mysql -u${MYSQL_ROOT_USERNAME} -p${MYSQL_ROOT_PASSWORD}
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 3699
Server version: 8.0.26-16.1 Percona XtraDB Cluster (GPL), Release rel16, Revision b141904, WSREP version 26.4.3
Copyright (c) 2009-2021 Percona LLC and/or its affiliates
Copyright (c) 2000, 2021, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
# value of `max_conncetions` is same as provided
mysql> show variables like 'max_connections';
+-----------------+-------+
| Variable_name | Value |
+-----------------+-------+
| max_connections | 230 |
+-----------------+-------+
1 row in set (0.001 sec)
# value of `read_buffer_size` is same as provided
mysql> show variables like 'read_buffer_size';
+------------------+---------+
| Variable_name | Value |
+------------------+---------+
| read_buffer_size | 1064960 |
+------------------+---------+
1 row in set (0.001 sec)
# value of `innodb_log_buffer_size` is same as provided
mysql> show variables like 'innodb_log_buffer_size';
+------------------------+----------+
| Variable_name | Value |
+------------------------+----------+
| innodb_log_buffer_size | 17408000 |
+------------------------+----------+
1 row in set (0.001 sec)
mysql> exit
Bye
As we can see from above the configuration has been changed, the value of max_connections
has been changed from 250
to 230
and the read_buffer_size
has been changed 122880
to 1064960
also, innodb_log_buffer_size
has been changed from 16777216
to 17408000
. So the reconfiguration of the sample-pxc
database is successful.
Remove Custom Configuration
We can also remove existing custom config using PerconaXtraDBOpsRequest
. Provide true
to field spec.configuration.removeCustomConfig
and make an Ops Request to remove existing custom configuration.
Create PerconaXtraDBOpsRequest
Lets create an PerconaXtraDBOpsRequest
having spec.configuration.removeCustomConfig
is equal true
,
apiVersion: ops.kubedb.com/v1alpha1
kind: PerconaXtraDBOpsRequest
metadata:
name: pxops-reconfigure-remove
namespace: demo
spec:
type: Reconfigure
databaseRef:
name: sample-pxc
configuration:
removeCustomConfig: true
Here,
spec.databaseRef.name
specifies that we are reconfiguringpxops-reconfigure-remove
database.spec.type
specifies that we are performingReconfigure
on our database.spec.configuration.removeCustomConfig
is a bool field that should betrue
when you want to remove existing custom configuration.
Let’s create the PerconaXtraDBOpsRequest
CR we have shown above,
$ kubectl apply -f https://github.com/kubedb/docs/raw/v2024.11.18/docs/guides/percona-xtradb/reconfigure/cluster/examples/reconfigure-remove.yaml
perconaxtradbopsrequest.ops.kubedb.com/pxops-reconfigure-remove created
Verify the new configuration is working
If everything goes well, KubeDB
Enterprise operator will update the configSecret
of PerconaXtraDB
object.
Let’s wait for PerconaXtraDBOpsRequest
to be Successful
. Run the following command to watch PerconaXtraDBOpsRequest
CR,
$ kubectl get perconaxtradbopsrequest --all-namespaces
NAMESPACE NAME TYPE STATUS AGE
demo pxops-reconfigure-remove Reconfigure Successful 2m1s
Now let’s connect to a perconaxtradb instance and run a perconaxtradb internal command to check the new configuration we have provided.
$ kubectl exec -it -n demo sample-pxc-0 -- bash
Defaulted container "perconaxtradb" out of: perconaxtradb, px-coordinator, px-init (init)
bash-4.4$ mysql -u${MYSQL_ROOT_USERNAME} -p${MYSQL_ROOT_PASSWORD}
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 3699
Server version: 8.0.26-16.1 Percona XtraDB Cluster (GPL), Release rel16, Revision b141904, WSREP version 26.4.3
Copyright (c) 2009-2021 Percona LLC and/or its affiliates
Copyright (c) 2000, 2021, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
# value of `max_connections` is default
PerconaXtraDB [(none)]> show variables like 'max_connections';
+-----------------+-------+
| Variable_name | Value |
+-----------------+-------+
| max_connections | 151 |
+-----------------+-------+
1 row in set (0.001 sec)
# value of `read_buffer_size` is default
PerconaXtraDB [(none)]> show variables like 'read_buffer_size';
+------------------+---------+
| Variable_name | Value |
+------------------+---------+
| read_buffer_size | 131072 |
+------------------+---------+
1 row in set (0.001 sec)
# value of `innodb_log_buffer_size` is default
PerconaXtraDB [(none)]> show variables like 'innodb_log_buffer_size';
+------------------------+----------+
| Variable_name | Value |
+------------------------+----------+
| innodb_log_buffer_size | 16777216 |
+------------------------+----------+
1 row in set (0.001 sec)
PerconaXtraDB [(none)]> exit
Bye
As we can see from the configuration has changed to its default value. So removal of existing custom configuration using PerconaXtraDBOpsRequest
is successful.
Cleaning Up
To clean up the Kubernetes resources created by this tutorial, run:
$ kubectl delete perconaxtradb -n demo sample-pxc
$ kubectl delete perconaxtradbopsrequest -n demo pxops-reconfigure-config pxops-reconfigure-apply-config pxops-reconfigure-remove
$ kubectl delete ns demo