RAID 0, RAID 1, RAID 5, RAID 10

RAID stands for Redundant Array of Inexpensive (Independent) Disks.
On most situations you will be using one of the following four levels of RAIDs.

• RAID 0
• RAID 1
• RAID 5
• RAID 10 (also known as RAID 1+0)

This article explains the main difference between these raid levels along with an easy to understand diagram.

In all the diagrams mentioned below:

• A, B, C, D, E and F – represents blocks
• p1, p2, and p3 – represents parity

RAID LEVEL 0

Following are the key points to remember for RAID level 0.

• Minimum 2 disks.
• Excellent performance ( as blocks are striped ).
• No redundancy ( no mirror, no parity ).
• Don’t use this for any critical system.

RAID LEVEL 1

Following are the key points to remember for RAID level 1.

• Minimum 2 disks.
• Good performance ( no striping. no parity ).
• Excellent redundancy ( as blocks are mirrored ).

RAID LEVEL 5

Following are the key points to remember for RAID level 5.

• Minimum 3 disks.
• Good performance ( as blocks are striped ).
• Good redundancy ( distributed parity ).
• Best cost effective option providing both performance and redundancy. Use this for DB that is heavily read oriented. Write operations will be slow.

RAID LEVEL 10

Following are the key points to remember for RAID level 10.

• Minimum 4 disks.
• This is also called as “stripe of mirrors”
• Excellent redundancy ( as blocks are mirrored )
• Excellent performance ( as blocks are striped )
• If you can afford the dollar, this is the BEST option for any mission critical applications (especially databases).

Detect and Avoid IP Address Conflicts

IPv4 address conflicts are a common cause of problems with DHCP. No two computers on the network can have the same unicast IP address. If a computer is assigned the same unicast IPv4 address as another, one or both of the computers might become disconnected from the network.

To better detect and avoid potential conflicts, you can enable IPv4 address conflict detection by following these steps:
1. In the DHCP console, expand the node for the server you want to work with, right-click IPv4, and then click Properties.
2. On the Advanced tab, set Conflict Detection Attempts to a value other than 0. The value you enter determines the number of times the DHCP server checks an IP address before leasing it to a client. The DHCP server checks IP addresses by sending a ping request over the network.

Real World Example: A unicast IPv4 address is a standard IP address for class A, B, and C networks. When a DHCP client requests a lease, a DHCP server checks its pool of available addresses and assigns the client a lease on an available IPv4 address. By default, the server checks only the list of current leases to determine whether an address is available. It doesn’t actually query the network to see whether an address is in use.

Unfortunately, in a busy network environment, an administrator might have assigned this IPv4 address to another computer or an offline computer might have been brought online with a lease that it believes hasn’t expired, even though the DHCP server believes the lease has expired. Either way, you have an address conflict that will cause problems on the network. To reduce these types of conflicts, set the conflict detection to a value greater than 0.

Use the Wbadmin Backup Command Line Utility in Windows Server 2008

Wbadmin is the command-line counterpart to Windows Server Backup. You use Wbadmin to manage all aspects of backup configuration that you would otherwise manage in Windows Server Backup. This means that you can typically use either tool to manage backup and recovery.

After you’ve installed the Backup Command-Line Tools feature, you can use Wbadmin to manage backup and recovery. Wbadmin is located in the %SystemRoot%\System32\ directory. As this directory is in your command path by default, you do not need to add this directory to your command path.

You can run Wbadmin by following these steps:
1. Click Start, click All Programs, and then click Accessories to open the Accessories menu.
2. Start an elevated command prompt by right-clicking Command Prompt and then selecting Run As Administrator.
3. In the Command Prompt window, enter the necessary command text or run a script that invokes Wbadmin.

Wbadmin has a number of associated commands:
DELETE SYSTEMSTATEBACKUP Deletes the system state backup or backups from a specified location.
DISABLE BACKUP Disables scheduled daily backups so that they no longer run.
ENABLE BACKUP Enables or modifies a scheduled daily backup.
GET DISKS Lists the disks that are currently online for the local computer. Disks are listed by manufacturer name, type, disk number, GUID, total space, used space, and associated volumes. GET ITEMS Lists items contained in a specified backup.
GET STATUS Reports the status of the currently running backup or recovery job.
GET VERSIONS List details about the available backups stored in a specific location, including the backup time and backup destination.
START BACKUP Starts a one-time backup using the specified parameters. If no parameters are passed and scheduled backups are enabled, the backup uses the settings for scheduled backups.
START RECOVERY Initiates a recovery of volumes, applications, or files using the specified parameters.
START SYSTEMSTATEBACKUP Starts a system state backup using the options specified.
START SYSTEMSTATERECOVERY Starts a system state recovery using the specified parameters.
STOP JOB Stops the currently running backup or recovery job. Stopped jobs cannot be restarted from where they were stopped.

When you are working with Wbadmin, you can get help on available commands:
1.To view a list of management commands, type wbadmin /? at the command prompt.
2.To view the syntax for a specific management command, type wbadmin Command /?, where Command is the name of the management command you want to examine, such as wbadmin stop job /?.

When you work with Wbadmin, you’ll find that just about every command accepts parameters and specific parameter values that qualify what you want to work with. To see more clearly how this works, consider the following syntax example:

wbadmin get versions [-backupTarget:{VolumeName | NetworkSharePath}]
[-machine:BackupMachineName]

The brackets tell you that –backupTarget and –machine are optional. Thus, you could type the following to get information on recoverable backups on the local computer:

wbadmin get versions

You could type the following to get information on recoverable backups for C:

wbadmin get versions -backuptarget:f:

Or you could type the following to get information on recoverable backups for C on Server96:

wbadmin get versions -backuptarget:f: -machine:server96

Many Wbadmin commands use the –backupTarget and –machine parameters. The backup target is the storage location you want to work with, and can be expressed as a local volume name (such as F:) or as a network share path, such as \\FileServer32\backups\Server85. The –machine parameter identifies the computer you want to work with for backup or recovery operations.

Reminders not popping up in Outlook 2007

Summary

After performing Windows updates and installing Microsoft KB number 2583910 for Outlook 2007 a warning appears stating:
There was a problem reading one or more of your reminders. Some reminders may not appear.

Details

This is similar to the problem encountered when Microsoft Office 2010 SP1 was released.
In order to resolve this, please uninstall Microsoft update KB2583910
Once that is uninstalled, please start outlook.exe with the option /cleanreminders turned on.

Bytes, Kilo Bytes, Mega Bytes, Giga Bytes, Tera Bytes, Peta Bytes ......

Processor or Virtual Storage

· 1 Bit = Binary Digit

· 8 Bits = 1 Byte
· 1024 Bytes = 1 Kilobyte
· 1024 Kilobytes = 1 Megabyte
· 1024 Megabytes = 1 Gigabyte
· 1024 Gigabytes = 1 Terabyte
· 1024 Terabytes = 1 Petabyte
· 1024 Petabytes = 1 Exabyte
· 1024 Exabytes = 1 Zettabyte
· 1024 Zettabytes = 1 Yottabyte
· 1024 Yottabytes = 1 Brontobyte
· 1024 Brontobytes = 1 Geopbyte

·

Disk Storage

 1 Bit = Binary Digit
· 8 Bits = 1 Byte
· 1000 Bytes = 1 Kilobyte
· 1000 Kilobytes = 1 Megabyte
· 1000 Megabytes = 1 Gigabyte
· 1000 Gigabytes = 1 Terabyte
· 1000 Terabytes = 1 Petabyte
· 1000 Petabytes = 1 Exabyte
· 1000 Exabytes = 1 Zettabyte
· 1000 Zettabytes = 1 Yottabyte
· 1000 Yottabytes = 1 Brontobyte
· 1000 Brontobytes = 1 Geopbyte 

Recovering the System Menu Password in Dynamics GP

When you have logged into Dynamics GP, go to Microsoft Dynamics GP >> Tools >> Customize >> Report Writer and choose the product as Microsoft Dynamics GP. This will open GP in the Report Writer mode as shown below. Click on the Reports button in the Toolbar.
  
Click on the New button in the Report Writer window and enter the following details for the new report that you have decided to create.

Report Name	System Password Recovery
Series	System
Main Table	System Password Master
Using Key	SY_System_Password_Key1

The report definition window would look as shown below.

Now click on the Layout button. Add the Password field from the System Password Master table into the Body section of the report as shown below.
  
Close the report and choose Save on the prompt that shows up.
Click OK on the Report Definition window to close the report definition window as well. Now you should be noticing the new report that we had created in the Report Writer window as shown below.
  
Select the new report that we had created and click on the Print button. On the Report Destination window, choose to print the report on Screen and click on the OK button.
The report will print on the screen and it will display the decrypted system menu password on the report as shown below.

Archive missing in Outlook 2007

Archive is missing in File menu.

Solution:

1. Uninstall Outlook installed update named  "Update for Microsoft Office Outlook 2007 (KB2412171)".

• Go to Control Panel > Programs and Features 
• In Tasks pane, click View installed updates
• In search bar, type KB2412171, then right click > Uninstall

or 

2.  Can't find KB2412171 to uninstall, yet I have symptoms

• Look for update KB2509470, then right click > Uninstall
• Restart
• Check the installed updates again, KB2412171 would appear then right click > Uninstall
• Restart

The Archive item will then appear in the File menu.