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Hierarchy Level


Define parameters for the configuration databases.

Configure the virtual-memory-mapping statement hierarchy to increase the memory space available for the configuration database size per process, as needed, by using virtual memory mapping and page-pooling.

Configure the ephemeral statement hierarchy to specify options for the ephemeral configuration database.

Configure the resize statement hierarchy when it is necessary to resize the configuration database.



Configure settings for the ephemeral configuration database. commit-synchronize-model specifies the commit model used to synchronize ephemeral data to the backup Routing Engine during a commit synchronize operation; instance sets the instance name; allow-commit-synchronize-with-gres enables a device to synchronize ephemeral configuration data to the other Routing Engine when GRES is enabled on the device and a commit synchronize operation is requested; and ignore-ephemeral-default disables the default instance of the ephemeral configuration database.


Increase the memory space available for the configuration database, per process, up to 1.5 GB. The extended default size is based on the original default database size. A device with a default database size of 409.99 MB will extend to a maximum of 1049.99 MB, and a device with a default database size of 665.99 MB will extend to a maximum of 1305.99.

The extend-size and max-db-size statements are mutually exclusive and cannot be configured together.

You must reboot the router after committing this statement to make the change effective.

Any operation on the system configuration-database extend-size configuration statement such as, deactivate, delete, or set, generates the following warning message:

Change in 'system configuration-database extend-size' will be effective at next reboot only.


The extend-size configuration statement is supported for Junos OS Evolved starting in release 22.1.

You should remove the extend-size statement before performing a rollback from Junos OS Evolved release 22.1 or later to any release prior to 22.1.


Configures the maximum database size. max-db-size and extend-size are mutually exclusive and cannot be configured together.


Resizes the configuration database. The database will be resized automatically during the commit based on the values specified in the database-size-diff and database-size-on-disk attributes. The system will display Database resize completed when the configuration database has been successfully resized.


Define parameters for using virtual memory mapping for the configuration database on a per-process basis. You can define a fixed size for the initial portion of the database and configure a page-pooling size for the remaining portion of the database. The parameter process sets the process name, while fixed-size sets the size in kilobytes to directly map for the initial portion of the configuration database for the specified process and page-pooling-size sets the size in kilobytes to use for page-pooling the remaining data in the database, with the valid range being from 512KB to 680MB for each.


Junos OS Evolved does not support the virtual-memory-mapping option.

The remaining statements are explained separately. See CLI Explorer.

Required Privilege Level

admin—To view this statement in the configuration.

admin-control—To add this statement to the configuration.

Release Information

Statement introduced in Junos OS Release 13.2.