Monitoring the Management Instances

Management instances store metadata used to manage the grid. It is recommended that you use an active and a standby instance to have high availability for this metadata. If you use a single management instance and that management instance is down, the grid continues to operate but you cannot perform certain management operations for your grid.

A management instance can get full because it stores information about your grid, previous grid model versions, and logs of your grid. It is important for the management instances to have enough free space to function properly. If your management instance begins to get full, any command that you run with the ttGridAdmin utility outputs a warning.

You can perform these tasks to maintain the management instances:

Modify the Retention Values of Previous Grid Models

This topic shows how to increase or decrease the retention values of previous grid models.

This example sets the retention days value to 60 and the retention versions value to 15. These values ensure that TimesTen Scaleout only deletes previous grid models that are older than 60 days and are at least 16 grid model versions old.

Note:

If you specify either the -retainDays or the -retainVersions parameter as 0, then only the other parameter is used. If you set both parameters values to 0, TimesTen Scaleout never automatically deletes previous grid model versions.

% ttGridAdmin gridModify -retainDays 60 -retainVersions 15
Grid Definition modified.

For more information about the ttGridAdmin gridModify command, see Modify Grid Settings (gridModify) in Oracle TimesTen In-Memory Database Reference.

Monitor the Free Space of the Management Instance

When you create a grid, the grid sets a used-space warning threshold for the management instance. If the size of your management instance reaches this threshold, commands that you run with the ttGridAdmin utility output warnings that the management instance is getting full.

This example shows the output of a ttGridAdmin instanceCreate command for a grid where the management instance is almost full.

% ttGridAdmin instanceCreate host9 -location /grid
Instance instance1 on Host host9 created in Model
Warning: the TTGRIDADMIN database is 91% full; Temp space: 57%

Note:

When you use a ttGridAdmin command and you see a warning that your management instance is getting full, TimesTen Scaleout deletes old grid model versions and logs based on the retention days and retention versions parameters of your grid.

Use the gridDisplay command of the ttGridAdmin utility on your management instance to see the current used-space warning threshold for the management instance, and retention days and quantity of previous versions of the grid model that TimesTen Scaleout stores.

This example shows the output of the ttGridAdmin gridDisplay command.

% ttGridAdmin gridDisplay
Grid name:                  grid1
Grid GUID:                  864C0CB2-AF40-4047-A711-7A9F9F0E7D6C
Created:                    2018-12-12 12:20:32.000000
Major Release:              22.1
Created Release:            22.1.1.18.0
K:                          3
Admin Userid:               terry
Admin UID:                  4133
Admin Group:                admin
Admin GID:                  900
Retain Days:                30
Retain Versions:            10
Warn Threshold:             90
Perm In Use Pct:            91
Temp In Use Pct:            57

For more information about the ttGridAdmin gridDisplay command and the default values for the retention of previous grid models and warning threshold of the management instance, see Display Information About the Grid (gridDisplay) and Modify Grid Settings (gridModify), respectively, in Oracle TimesTen In-Memory Database Reference.

See Resize the Management Instance for more information on resizing the grid administration database.

Modify the Used-Space Warning Threshold of the Management Instances

This topic shows how to increase or decrease the current used-space warning threshold for the management instances.

This example sets the current used-space warning threshold for the management instances to 80%.

% ttGridAdmin gridModify -warnThresh 80
Grid Definition modified.

For more information about the ttGridAdmin gridModify command, see Modify Grid Settings (gridModify) in Oracle TimesTen In-Memory Database Reference.

Resize the Management Instance

In some cases, you may want to resize the management instance because it is getting full.

Depending on if your grid has a single management instance or an active and a standby management instances, follow one of these procedures:

Grid with a Single Management Instance

To resize the management instance of a grid with one management instance, ensure that you are connected to the management instance.

Export the database definition.

% ttGridAdmin dbdefExport TTGRIDADMIN /tmp/ttgridadmin.dbdef

The following example shows the contents of the exported file.

[TTGRIDADMIN]
AutoCreate=0
Connections=100
DBUUID=C12C4FAE-5732-4307-A08F-5F7FBF9BF1C0
DataStore=!!TIMESTEN_HOME!!/grid/admin/database/!!TTGRIDADMIN!!
DatabaseCharacterSet=AL32UTF8
DurableCommits=1
LockWait=120
Overwrite=0
PLSQL=1
PLSQL_TIMEOUT=0
PermSize=200
TempSize=100

With a text editor, modify the value of the PermSize connection attribute to a larger value.

The following example shows the contents of the modified database definition file. In this example, the new value of the PermSize connection attribute is 400.

[TTGRIDADMIN]
AutoCreate=0
Connections=100
DBUUID=C12C4FAE-5732-4307-A08F-5F7FBF9BF1C0
DataStore=!!TIMESTEN_HOME!!/grid/admin/database/!!TTGRIDADMIN!!
DatabaseCharacterSet=AL32UTF8
DurableCommits=1
LockWait=120
Overwrite=0
PLSQL=1
PLSQL_TIMEOUT=0
PermSize=400
TempSize=100

Import the contents of the modified database definition file into the TTGRIDADMIN database definition.
```
% ttGridAdmin dbdefModify /tmp/ttgridadmin.dbdef
Database Definition TTGRIDADMIN modified.
```

Apply the changes of the TTGRIDADMIN database definition file to the current version of the model.

% ttGridAdmin modelApply
...
Pushing new configuration files to each Instance......................OK
...
ttGridAdmin modelApply complete

Stop the management instance.
Note:

Stopping the management instance does not impact existing databases. However, you are unable to perform management operations until you start the management instance.
```
% ttGridAdmin mgmtActiveStop
Active management instance stopped
```

Start the management instance.

% ttGridAdmin mgmtActiveStart
This management instance is now the active

You have successfully resized your management instance.

Grid with Active and Standby Management Instances

To resize the management instances of a grid with active and standby management instances, ensure that you are connected to the active management instance.

Export the database definition of the grid administration database.

% ttGridAdmin dbdefExport TTGRIDADMIN /tmp/ttgridadmin.dbdef

The following example shows the contents of the exported file.

[TTGRIDADMIN]
AutoCreate=0
Connections=100
DBUUID=C12C4FAE-5732-4307-A08F-5F7FBF9BF1C0
DataStore=!!TIMESTEN_HOME!!/grid/admin/database/!!TTGRIDADMIN!!
DatabaseCharacterSet=AL32UTF8
DurableCommits=1
LockWait=120
Overwrite=0
PLSQL=1
PLSQL_TIMEOUT=0
PermSize=200
TempSize=100

With a text editor, modify the value of the PermSize connection attribute to a larger value.

The following example shows the contents of the modified database definition file. In this example, the new value of the PermSize connection attribute is 400.

[TTGRIDADMIN]
AutoCreate=0
Connections=100
DBUUID=C12C4FAE-5732-4307-A08F-5F7FBF9BF1C0
DataStore=!!TIMESTEN_HOME!!/grid/admin/database/!!TTGRIDADMIN!!
DatabaseCharacterSet=AL32UTF8
DurableCommits=1
LockWait=120
Overwrite=0
PLSQL=1
PLSQL_TIMEOUT=0
PermSize=400
TempSize=100

Import the contents of the modified database definition file into the TTGRIDADMIN database definition.
```
% ttGridAdmin dbdefModify /tmp/ttgridadmin.dbdef
Database Definition TTGRIDADMIN modified.
```

Apply the changes of the TTGRIDADMIN database definition file to the current version of the model.

% ttGridAdmin modelApply
...
Pushing new configuration files to each Instance......................OK
...
ttGridAdmin modelApply complete

From the standby management instance, stop the management instance.
Note:

This procedure does not impact existing databases or affect operations of the grid.
```
% ttGridAdmin mgmtStandbyStop
Standby management instance host2.instance1 stopped
```
From the standby management instance, start the management instance.
```
% ttGridAdmin mgmtStandbyStart
Standby management instance started
```
From the standby management instance, promote the standby management instance to be the new active management instance and shut down the original active management instance.
```
% ttGridAdmin mgmtActiveSwitch
This is now the active management instance
```
From the original active management instance, start the new standby management instance.
```
% ttGridAdmin mgmtStandbyStart
Standby management instance started
```

You have successfully resized your management instances. Additionally, your original active management instance is now the standby management instance and the original standby management instance is now the active management instance. This does not affect operations of your grid.