Newisys NA-1400, User Manual

Page: 62 / 64

Glossary
62 NA-1400
Snapshot
A "frozen" image of a volume that represents the status of a volume in a given instance. This image can be
used for backups.
Software RAID Appliance
An NA-1400 that uses a Redundant Array of Independent Disks (RAID) as the storage medium. In a
Software RAID appliance the disk array is controlled and maintained by Web interface software, so that no
RAID controller card is necessary. All information that is stored on the NA-1400 will be contained in the
RAID. The NA-1400 offers Software RAID levels 0, 1, and 5.
Storage object
Any memory structure in EVMS that is capable of being a block device. (See also EVMS and Status.) An
administrator can view status information about the NA-1400 through the Web interface. The administrator
can view available and used space on each partition of the NA-1400, user connections to the NA-1400,
NA-1400 status, and NA-1400 name.
Subnet Mask
The number (formatted similar to an IP address) that is used to define a sub-network, so that IP addresses
can be shared on a Local Area Network. If the Server Appliance has a static IP address, the Subnet Mask
must be entered in the Web interface.
Transmission Control Protocol/ Internet Protocol (TCP/IP)
The protocol that most computers use for communication on the Internet and Local Area Networks
(LANs). TCP/IP is comprised of two distinct parts. The Transmission Control Protocol (TCP) establishes a
connection with both the server and client ends, and passes data to the connectionless Internet Protocol
(IP). TCP is responsible for correct delivery of data from one computer to another. If data is lost en route to
the destination, TCP retransmits until the data is received successfully, or until a timeout occurs. The
Internet Protocol is responsible for actually moving data from one node of the network to another.
Therefore, each packet of data is forwarded to the correct IP address using the Internet Protocol.
Uninterruptible Power Supply (UPS)
An AC-powered battery into which computers are plugged. The purpose of a UPS is to allow a computer to
shut down safely when power is lost unexpectedly. NA-1400 server software has built-in UPS support so
that when the power cord and a serial cable are plugged in a supported UPS, the built-in can safely
shutdown, if the battery level becomes critical in a power outage. This ensures that no data is lost during
power outages.
UNIX
An operating system that is widely used on servers in a variety of contexts, including the Internet. UNIX is
multi-user (multiple users can access a UNIX-based system at the same time), thus well-suited to running a
server. Clients who wish to log on to a UNIX server must be running UNIX-based operating systems or
must have programs that allows their workstations to use NFS. The NA-1400 server is based on the Linux
operating system.
User Authentication Types
The NA-1400 offers three methods for user authentication.
• Users Authenticated on the NA-1400 (NA-1400 Server Mode) In this method of authentication, all
user and group information is created and maintained on the hard drive of the NA-1400. Therefore,
each time a user attempts to connect to a private share on the NA-1400, the NA-1400 software verifies
that the user is allowed to access the share.