DR Series Software 4.0.3 - Administration Guide

DR Series System NVRAM

NVRAM is a field replaceable unit (FRU) in the DR Series system (Note: NVRAM is not part of the DR4300e Core system). The super capacitor that powers the NVRAM double-data rate (DDR) memory must be able to move its contents to the solid-state drive (SSD) during a power loss.

This data transfer requires maintaining the power to run the system for 3 minutes of operation (normally, it only takes approximately one minute). If a problem occurs during the data backup to the SSD, the subsequent system reboot detects this. NVRAM can experience backup failure when the following occurs:

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The NVRAM failed to backup the data during the power shutdown

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The super capacitor did not maintain sufficient power to backup the DDR contents into the SSD.

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The NVRAM/SSD encountered an end-of-line (EOL) or another error.

If any of these conditions occur, the NVRAM requires either a failure recovery or a replacement.

NOTE: Quest recommends the following supported method for flushing DR Series system data from the NVRAM to the RAID6 before replacing the NVRAM by using either of the following DR Series system CLI commands: system --shutdown or system --reboot.

NOTE: If you need to remove or replace the NVRAM in the DR Series system, see the topics, Shutting Down the DR Series System and NVRAM Field Replacement.

NVRAM Backup Failure Recovery

After you have physically replaced the NVRAM card in a PCIe x4 (or x8) slot in the DR Series system chassis, you can recover from an NVRAM backup failure by completing the following tasks:

CAUTION: You must wait a minimum of 20 minutes after powering on the DR Series system before using the DR Series system CLI maintenance --hardware --reinit_nvram command. This 20–minute post power-on waiting period allows the NVRAM card, the super capacitor calibration, and all solid state drive (SSD) processes to fully complete, which are necessary for the proper operation of the DR Series system.

During Maintenance mode, the DR Series system determines, detects, and repairs the data loss. During the system reboot process, it ensures that no valuable data remains on the NVRAM.

Enter the following DR Series system CLI command: maintenance --hardware --reinit_nvram.

This formats the SSD and clears all of the backup and restore logs, by reinitializing the NVRAM.

Verify that the DR Series system enters its Maintenance mode.

For more information about replacing the NVRAM, see NVRAM Field Replacement and DR Series System: Proper Shut Down and Start Up.

NVRAM Field Replacement

Whenever the DR Series system NVRAM is replaced in the field, you must observe this best practice procedure:

CAUTION: You must wait a minimum of 20 minutes after powering on the DR Series system before using the DR Series system CLI command: maintenance --hardware --reinit_nvram. This post power-on waiting period allows the NVRAM card, the super capacitor calibration, and the SSD processes to fully complete, which are necessary for the proper operation of the DR Series system.

NOTE: For more information, see DR Series System: Proper Shut Down and Start Up.

Verify that the DR Series system software detects the NVRAM as being new to the system.

Enter the following DR Series system CLI command: maintenance --hardware --reinit_nvram.

This command initializes the NVRAM, creates new partitions, and updates information used internally by the DR Series system software.

Verify that the DR Series system enters its Maintenance mode.

If properly initialized, the DR Series system will automatically enter Maintenance mode. The filesystem checker examines every blockmap and datastore to determine how much data was lost due to the failed NVRAM.