Manager Handbook for Centralized AntDB-T — P2–2
Published: 2023-08-11 07:24:28


**_Manager Handbook for Centralized AntDB-T - P2–2_**

**Parameter description**

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/obhbs705rsd7tzmm2n16.png)

**Send a SQL command**
patronictl can send query command to the cluster to execute the corresponding SQL text.

```
#In the following command, "postgres-cluster" is the cluster name, and "-d postgres" refers to the database name.[adbpuq@host-10-19-28-129 ~]$ patronictl -c /etc/patroni.yml query postgres-cluster --command 'select version() ' -d postgres
version
PostgreSQL 13.3 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-44), 64-bit
```

**Get the master node dsn information**
patronictl can get the dsn information of the master node with the dsn command. The dsn is followed by the cluster name.

```
[adbpuq@host-10-19-28-129 ~]$ patronictl -c /etc/patroni.yml dsn postgres-cluster 
host=10.19.36.207 port=55551 
```


**Delete cluster information in DCS**
The patronictl followed by the remove command removes the cluster, as shown below, removing the batman5 cluster information.

```
patronictl -c /etc/patroni/patroni.yml remove batman5 
+---------+--------+------+------+-------+-----------+  
| Cluster | Member | Host | Role | State | Lag in MB |  
| batman5 | antdb117 | 10.21.20.117:6432 | Leader | running | 22 |0.0 | 
| batman5 | antdb118 | 10.21.20.118:6432 | | running | 22 |0.0 | 
| batman5 | antdb119 | 10.21.20.119:6432 | | running | 22 |0.0 | 
Please confirm the cluster name to remove: batman5 
You are about to remove all information in DCS for batman5, please type: "Yes I am aware": Yes I am aware 
```

**Reboot the cluster**
patronictl’s restart directly followed by the cluster name can restart the cluster. — force can force a cluster restart.
```
[adbpuq@host-10-19-28-129 ~]$ patronictl -c /etc/patroni.yml restart postgres-cluster
+----------+--------------------+--------------+---------+-----+-----------+
| Member   | Host               | Role         | State   |  TL | Lag in MB |
+ Cluster: postgres-cluster (7171609184693121315) -------+-----+-----------+
| pgnode01 | 10.19.28.129:55551 | Replica      | running | 467 |         0 |
| pgnode02 | 10.19.36.206:55551 | Sync Standby | running | 467 |         0 |
| pgnode03 | 10.19.36.207:55551 | Leader       | running | 467 |           |
+----------+--------------------+--------------+---------+-----+-----------+
When should the restart take place (e.g. 2022-12-27T16:11)  [now]:
Are you sure you want to restart members pgnode03, pgnode01, pgnode02? [y/N]: y
Restart if the PostgreSQL version is less than provided (e.g. 9.5.2)  []:
Success: restart on member pgnode03
Success: restart on member pgnode01
Success: restart on member pgnode02

#--Force restart
[adbpuq@host-10-19-28-129 ~]$ patronictl -c /etc/patroni.yml restart postgres-cluster --force
+----------+--------------------+--------------+---------+-----+-----------+
| Member   | Host               | Role         | State   |  TL | Lag in MB |
+ Cluster: postgres-cluster (7171609184693121315) -------+-----+-----------+
| pgnode01 | 10.19.28.129:55551 | Sync Standby | running | 467 |         0 |
| pgnode02 | 10.19.36.206:55551 | Replica      | running | 467 |         0 |
| pgnode03 | 10.19.36.207:55551 | Leader       | running | 467 |           |
+----------+--------------------+--------------+---------+-----+-----------+
Success: restart on member pgnode03
Success: restart on member pgnode01
Success: restart on member pgnode02

```


**Restart the nodes**
patronictl’s restart directly followed by the cluster name and the node name can restart the node in the cluster. — force can force a cluster restart.
```
[adbpuq@host-10-19-28-129 ~]$ patronictl -c /etc/patroni.yml restart postgres-cluster pgnode01
+----------+--------------------+--------------+---------+-----+-----------+
| Member   | Host               | Role         | State   |  TL | Lag in MB |
+ Cluster: postgres-cluster (7171609184693121315) -------+-----+-----------+
| pgnode01 | 10.19.28.129:55551 | Sync Standby | running | 467 |         0 |
| pgnode02 | 10.19.36.206:55551 | Replica      | running | 467 |         0 |
| pgnode03 | 10.19.36.207:55551 | Leader       | running | 467 |           |
+----------+--------------------+--------------+---------+-----+-----------+
When should the restart take place (e.g. 2022-12-27T16:19)  [now]:
Are you sure you want to restart members pgnode01? [y/N]: y
Restart if the PostgreSQL version is less than provided (e.g. 9.5.2)  []:
Success: restart on member pgnode01

#--Force restart
[adbpuq@host-10-19-28-129 ~]$ patronictl -c /etc/patroni.yml restart postgres-cluster pgnode01 --force
+----------+--------------------+--------------+---------+-----+-----------+
| Member   | Host               | Role         | State   |  TL | Lag in MB |
+ Cluster: postgres-cluster (7171609184693121315) -------+-----+-----------+
| pgnode01 | 10.19.28.129:55551 | Replica      | running | 467 |         0 |
| pgnode02 | 10.19.36.206:55551 | Sync Standby | running | 467 |         0 |
| pgnode03 | 10.19.36.207:55551 | Leader       | running | 467 |           |
+----------+--------------------+--------------+---------+-----+-----------+
Success: restart on member pgnode01

```



**Reinitialize the nodes**
The reinit of patronictl followed by the cluster name and selecting the corresponding node can reinitialize a node of the cluster. — force can force a re-initializetion.

```
# You can choose the node(s) to be restarted in the interactive options.
[adbpuq@host-10-19-28-129 ~]$ patronictl -c /etc/patroni.yml reinit postgres-cluster
+----------+--------------------+--------------+---------+-----+-----------+
| Member   | Host               | Role         | State   |  TL | Lag in MB |
+ Cluster: postgres-cluster (7171609184693121315) -------+-----+-----------+
| pgnode01 | 10.19.28.129:55551 | Replica      | running | 467 |         0 |
| pgnode02 | 10.19.36.206:55551 | Sync Standby | running | 467 |         0 |
| pgnode03 | 10.19.36.207:55551 | Leader       | running | 467 |           |
+----------+--------------------+--------------+---------+-----+-----------+
Which member do you want to reinitialize [pgnode02, pgnode03, pgnode01]? []: pgnode01
Are you sure you want to reinitialize members pgnode01? [y/N]: y
Success: reinitialize for member pgnode01

# You can also directly input the node(s) that need to be re-initialized in the command line. The option "--force" can be used to force re-initialization.
[adbpuq@host-10-19-28-129 ~]$ patronictl -c /etc/patroni.yml reinit postgres-cluster pgnode01 --force
Success: reinitialize for member pgnode01
```



**Parameter modification**
The parameters are obtained with a certain priority: patroni’s memory (patronictl -c /etc/patroni.yaml edit-config) > patroni’s local configuration (/etc/patroni.yaml) > postgresql.auto.conf > postgresql. conf > postgresql.base.conf.
Among them, the edit-config command of patronictl has the highest priority for editing parameters, and you need to restart the cluster after editing.

```
patronictl -c /etc/patroni.yml edit-config 
patronictl -c /etc/patroni.yml restart postgres-cluster --force
```