Network disk arrays of company Maxtronic

By Andrey Ryakhin

Until recently for storage in local network and teamwork with the general data (without any dependence from their type), as a rule, were bought expensive servers with necessary disk capacity, and on these servers OS Windows was normally put. Thus for their service the staff of system managers which took care for them, carried out the preventive maintenance and put upgrades was recruited. Both all was good, and everyone was pleased, while someone was occurred with a simple idea. And what for, as a matter of fact, to use expensive servers with rather expensive (if for it to pay, certainly) the software if such server carries out only rather simple problems of data sending and acquisition? Really when servers are basically used for data storage (so-called file servers) the payload of the processor is insignificant, and the little RAM is necessary. But thus as it is ridiculous, the big resources leave on support of functioning of operational system actually. In result some years back the special devices have appeared, which officially refer to as NAS (Network Attached Storage), or in another way — ready-to-use file servers.

Idea of NAS is rather simple — actually, it is the general computer with operational system interweaving in memory (normally it is any clone of Linux). But those parts of operational system which are intended for service of all NAS functions are only interweaved, therefore the volume of such operational system does not exceed 32 MB. RAIDs of various levels of data storage are supported, but again by the software. Due to interweaving of the operational system in the RAM, follows rather the important feature of NAS: the system extremely difficultly to break open outside. Such optimization of operational system exceptionally under needs of a file server results in high speed of NAS, even despite of RAID program organization.

In systems of TV production and broadcasting the actuality of network solutions is constantly grown. It is defined both of the general increase of information streams of digital data, and complication of the modern TV projects demanding more and more harmonious operation of creative groups. One of typical examples is the production of serials. Along with extremely condensed deadlines the computer editing of series is normally carried out during some shifts, and simultaneously on several machines. And efficiency of storage and sharing of the general data appears as the crucial factor. Not without reason in modern professional editing programs, for example in versions of Pinnacle Liquid Edition Broadcast and higher, the opportunity of operation in a network with an uniform disk array is highlighted with the first line indent.

In this connection for building of network file to the choice of optimum solution the special attention was given. After the carried out studies we have stopped on NAS devices of Taiwan company Maxtronic International, and the best sample by the criterion price/efficiency is Pegasus 820GR. This system is designed for eight hard disks IDE, that is the maximal visible volume is equal to 1.75 TB (for disks of 250 MB at RAID-level 3 or 5).

Base technical features of the device are given in the table.

One of the basic questions who may arise at the user, — what the exchange rate is with such device? For the network systems participating in operation with video or other stream media data, the exchange rate has rather essential, and in some cases and crucial importance. For achievement of the greatest possible exchange rate the Pegasus 820GR has two Gigabit network controllers. Network controllers may operate as with individual adjustments for each controller, and in one of three modes supporting one logic channel: Trunking (doubling of throughput), Fail-Over (one controller is in “hot” reserve and is put into operation in case of failure of another) and ALB (Automatic Load Balance). Last mode provides intellectual distribution of load between controllers according to the traffic.

Under correct configuration of a network the operation in mode Trunking or ALB may enable the stream recording up to 50 MB/sec that is very high feature of the network device.

Configuration of Pegasus 820GR is very simple also does not demand the presence of the highly skilled system manager. First, it is possible simply to transfer all adjustments from a Windows-server over SMB; second, hand-held adjustment through any web-browser is intuitively clear and simple. In service the NAS is also extremely undemanding: there is no necessity for updating of its operational system, installation of any program-patches and fresh drivers. The additional advantage of the system is an opportunity of Pegasus 820GR operation in networks with Apple computers.

In summary once again it would be desirable to emphasize, that Pegasus 820GR is a bright representative of rather new class of NAS devices doomed for the success at Russian markets. And if by the price a big difference between Pegasus 820GR and a similar file server on platform Intel is not present, by simplicity of service and reliability of operation the NAS noticeably surpass any common server with the installed server operational system. If it is necessary to pay for the server software, price of NAS is out of competition. As to free-of-charge Linux its installation demands really high qualification of the manager.

Thus, application of NAS gives much more effective and economic solution of a problem of network storage and an exchange of any data, including digital video.

Material provided by Stoik Company