RAID 1, also known as disk mirroring, is a level of RAID in which data is duplicated on both disks of an array. RAID 1 requires two disk volumes in the array. With RAID 1, each disk is a mirror of the other disk. Because disks are mirrored, there will need to be an even […]

RAID 0, also known as disk striping, is a level of RAID that distributes blocks of data to the disks within the RAID. This level of RAID can be accomplished using two or more disk drives. With RAID 0, the blocks of data are roughly distributed equally among each of the disks. The storage capacity […]

The main configuration file for Apache is located at /etc/apache2/apache2.conf. Apache may work a little different on Ubuntu (and other Debian based distributions) than other operating systems when it comes to adding and removing modules as well as virtual host configuration. The differences are the result of an effort to make it more flexible and […]

Parity is a function of RAID in which an XOR result of at least two striped blocks is calculated and stored on an additional block. This requires at least three drives. Two of the drives will contain striped block data, the remaining drive will contain a parity block. How parity works Assume we have three […]

Mirroring is a function of RAID in which data stored on one drive is duplicated on another drive. This creates redundant identical copies of data. There must be two physical drives in a set. Because data is duplicated to both drives, there is no gain in write speeds. Advantages to Mirroring With mirroring, if one […]

Striping is a function in RAID that distributes data across multiple physical drives. Data can be striped at a bit or block level. Block sizes of data typically range between 4 and 128 KB blocks. Many systems default to 64KB blocks. Determine the best stripe size You will first need to determine the average file […]

Apache is currently the most commonly used and trusted web server application. It has dominated as the primary web server software. In this lesson we will learn to install the application as well as setup firewall rules to allow it server web pages to clients. Installing Apache Before we install Apache, it will be a […]

The term “software RAID” refers to using an operating system to accomplish RAID. The operating system makes the RAID volume available during the boot up process. Most of the well known operating systems provide software to accomplish RAID. In Windows operating systems you can create a RAID array using the Disk Management tool. This applies […]

The term “hardware RAID” refers to using dedicated hardware to accomplish RAID. This is typically done by adding a RAID controller to an expansion port on the motherboard. The RAID controller will have it own processing controllers to handle the RAID. Servers that are designed for multiple disk drives usually have a RAID controller card […]