Viewing Reports and Logs : Viewing Disk Status Reports
  
Viewing Disk Status Reports
The Disk Status report appears on Fault Tolerant Storage (FTS) enabled SteelHead models to alert you to a disk failure or recovery.
SteelHeads using Solid-State Disk (SSD) technology to store optimization data also use FTS.
FTS technology is a high-performance alternative to RAID and has these benefits:
•  Service reliability - FTS allows the SteelHead to continue working at full operating speed after a drive failure with the remaining drives. The optimization data store is slightly smaller until you replace the failed SSD.
FTS-enabled SteelHead can optimize traffic up to the point that every data store drive fails.
•  Performance - When you replace the failed SSD, the data store returns to its original size.
A disk failure or recovery can occur when the optimization service is:
•  not running.
•  running, but idle because there’s no traffic.
•  handling optimized connections but not using the disk.
•  writing to the disk.
•  reading from the disk.
The Disk Status report includes this information.
Column
Description
Disk
Displays the disk number.
Status
Displays the disk status:
•  Degraded - Indicates a failure of one or more of the RAID arrays. The disk itself has not failed.
•  Failed - Indicates the disk has failed. The alarm email notification denotes whether the failure is on a management or data store disk. The optimization service continues to run normally without interruption or dropped connections when a single disk fails, albeit with reduced data store capacity and performance degradation.
This message can also indicate that a disk has been inserted into an incorrect slot or that the disk has already been used in another SteelHead.
If all disks fail, the optimization service halts.
Consult the system log for more information.
Riverbed replaces the failed component at Riverbed’s expense as long as the device is covered by a current support contract. Depending on the level of support contract, a trained engineer could be on site with the replacement part within four hours. If the report displays a failed disk status, go to Riverbed Support at https://support.riverbed.com.
•  Missing - There is no disk in the slot.
•  Rebuilding - The disk is rebuilding after it has been inserted into the slot. Rebuilding a data store disk takes approximately one hour or less to rebuild; a management disk that is part of a RAID mirror can take longer (4-6 hours). The status continues to be rebuilding until the drive is completely rebuilt.
•  Online - Disk is up and working.
Task
Displays the system component the disk is used for: either data store or management. If the disk is used for both, the task column doesn’t appear.
What This Report Tells You
The Disk Status report answers these questions:
•  How many disks are on the SteelHead?
•  What’s the current status of each disk?
•  What function is the disk performing?
To view the Disk Status report
•  Choose Reports > Diagnostics: Disk Status to display the Disk Status page. This menu item appears only on SteelHead models using Solid State Disks (SSDs).
Figure: Disk Status Page
To print the report, choose File > Print in your web browser to open the Print dialog box.