This article gives basic information for the levels RAID 5 and RAID 6 of storage virtualization technology. It compares the level of protection and the performance provided by the different array configurations.
Hot spare is a drive that acts as a stand by drive in RAID 1, RAID 5 or RAID 6 volume. It is fully functional drive that contains no data and is not used during normal operation. If a drive from the volume fails, the controller reconstructs the data from the failed drive to the hot spare drive.
A RAID 5 array is designed to protect against the failure of a single disk within the array. Because of the way that RAID 5 works, the total capacity of one disk is lost to overhead. If, for example, a RAID 5 array contained five 10TB disks, then the array’s usable capacity would be 40TB.
A RAID 5 (with Hot Spare disk) array can be configured to treat one of the disks as a hot spare. Then one of the disks is reserved as a replacement in the event that a disk fails. For the above example with five 10TB disks, this would decrease the example array’s usable capacity to 30TB.
A RAID 6 array is designed to protect against two simultaneous disk failures. However, the price for this extra protection is that two disks' worth of capacity is lost to overhead. As such, a RAID 6 array made up of five 10TB disks would have a usable capacity of 30TB because 20 TB is lost to overhead.
The performance during Normal Operation is measured in IOPS (Input/output operations per second) and as a sum for all the disks (excluding the Hot Spares and decreased for writing parity data) in the array. As a rule of the thumb, the higher the overhead associated with writing parity data (in the above example RAID 5 with Hot Spare causes the same overhead like RAID 6) the lower the IOPS.
The reason for implementing RAID arrays is to secure the data. The level of protection does not directly correlate with the overhead. From the above example both RAID 5 with Hot Spare and RAID 6 have same capacity, but offer different level of protection. In case of failure of RAID 5 array with Hot Spare, the Hot Spare is activated and the rebuild process start immediately. The system can recover from a single disk failure and during the recovery, process is vulnerable to second disk failure. Therefore, RAID 5 and RAID 5 with Hot Spare disk offer the same level of protection – single disk failure. In contrast, if a disk fails at RAID 6 array, the recovery will start only after the faulty disk is replaced manually. However, if during the recovery process second disk fails, the RAID 6 array will stay functional.
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Level confidentiality: external
Related Products: Video SDK
Analyzing issues with Video SDK based application is a challenging task. One needs to determine if the issue is based on wrong implementation of the Video SDK functionality, wrong programming practices, functionality and runtime behavior of the system with SDK functionality or Video SDK issues. In order to start troubleshoot Video SDK application support needs the following initial information and logging.
Please prove the following information to support.
2.VideoSDK issue description
What is the expected behavior?
What is the issue?
Which shared resources are accessed by SDK actions? (Dome cameras, decoders, etc.)
Do SDK components interact with an unreliable environment? (Unstable network, offline devices, offline PCs, etc.)
Do SDK components properly handle offline situations? (offline devices, configuration changes, ...)
Please provide source code and/or Log files
The optimal approach is to provide both source code and logging for the problematic Video SDK application.
1.Try to reproduce the issue with one of the Video SDK samples (Advanced C# Sample, Complete C# Sample, Simple C# Sample) and provide the result from the test.
Provide a little sample application that illustrates the Video SDK issue and list the reproduction steps.
Enable VideoSDK backdoor logging, reproduce the issue (note the date and time) and provide the Video SDK logs. How to collect Video SDK log files
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BVMS, Operator Client
This article describes the initial information needed to start troubleshooting Operator Client Crash.
Needed information and logs from the customer:
1. Note down the events that lead to crash
2. Classify the crash
reproducible crashes that trigger Windows Error Reporting
crashes/hangs/freezes that are hard to reproduce, or take long before repeating
3. Provide the following logs:
Dump file from the crash – refer to the following article ( https://community.boschsecurity.com/t5/Security-Video/How-To-create-BVMS-memory-dump/ta-p/7326 )
ConfigCollection from the machine where the crashing Operator Client is running.
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Workstations, Z4G4, Microsoft License
Is it possible to Activate Windows 10 by phone for Bosch Workstations?
With introduction of Windows 10, Microsoft disable the phone license activation for Bosch Workstations.
Please perform online activation over internet.
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