“The Gunma University Library and Information Technology Center uses QNAP products to store network log data. There have been no malfunctions or errors, and they operate securely.” - Gunma University Library and Information Technology Center
The Library and Information Technology Center at Gunma University (hereinafter called the Library and Information Technology Center) is the organization responsible for supporting IT activities and maintaining information security within the university.We asked assistant professor Hiroshi Ueda PhD (Eng), a network researcher at the center, for information about the circumstances surrounding the introduction of QNAP "TS-439U-RP" and its evaluation.
※Note: In this article, unless otherwise specified, the term "QNAP" refers to the QNAP "TS-439U-RP".
Outline of the Library and Information Technology Center
Tell us about the Library and Information Technology Center.
The Library and Information Technology Center was created by the merging of the existing information processing center and the library in 2005. It is engaged in basic IT structuring, IT and IT activities support and research, and the teaching of safe and effective use of the Gunma University network.
The Library and Information Technology Center is the network hub that structures, supervises and binds the four campuses of Gunma University to the ancillary schools.
The center has one professor, an assistant professor, four engineers and 30 office workers.
Assistant Professor Ueda, please tell us about yourself?
I supervise the planning, management, and security of the whole Gunma University network at the Library and Information Technology Center. In 2007, I set up and unified the basic network ID configuration throughout the university. As a consequence, I was able to combine the operations of the individual networks in three of the campuses, and introduce uniform user verification throughout all of them.
My personal research topic is the current problem of traffic fractals on the network. (※See Note 1.)
I published a document that analyzes the network entitled "Wireshark Packet Analysis Reference" through Softbank Creative in June 2009, a joint work with Professor Hisayonebara of the Library and Information Technology Center. The book was translated and published in Taiwan in 2010.
※1 Traffic fractals
Traffic bursts (waves) are characterized by not being lost even if the time granularity is rough.
Circumstances Surrounding the Introduction of QNAP
What are the reasons for using QNAP?
In December 2009, we installed and have been using QNAP in the server room to save network logs within the school.
※2 In storing log data, consideration is given to privacy and personal information for data storage, such as being limited to the headers, etc.
Why are network logs necessary?
There are three reasons for this.
It was necessary to determine how the network was currently being used for reference data when configuring future networks.
Next, we structured a firewall as a security measure. We decided that one link in this was to keep logs to maintain evidence.
Finally, long-term log data is necessary to clarify traffic fractals on the network as this is the subject of my research.
Why did you decide to introduce network-attached storage (NAS) for log storage?
When we initially started to store the logs, we used a PC server, but even with 1TB of memory storage space, data overflowed within a month. However, introducing a new PC server, was difficult on the grounds of cost.
NAS uses the same functions as a PC server and so special knowledge is not needed for it’s operation. NAS is the only product that isn't difficult to operate and this is one reason why we decided upon it’s introduction.
Requirements for Introducing NAS Products
Tell us the requirements for introducing NAS products.
1. Large capacity and low cost
The PC server we were using up to that time had rapidly became full and so large capacity was essential. Further, when the actual product is inexpensive, capacity can also be increased by allocating a budget for HDDs, so the low price was an advantage.
2. The ability to restart online if a data crash occurs
No one knows when a crash will occur. To restart quickly when data has been corrupted, it is necessary to replace the HDD and restart while remaining online.
3. Being able to perform RAID migration (※See Note 3.)
Being able to perform RAID migration enables migration to different RAID levels. If it becomes necessary in future to change the RAID level, this can be accomplished while maintaining full operation.
4. Must be rack mountable
As the products were to be placed in the server room, a full range of rack mountable models was necessary. Unless the devices are rack-mountable, installation becomes problematic.
5. NFS compatibility
We wanted to connect the NAS to the PC server used for the dumped data (※See Note 4) using NFS. The reason being that data transfer and management could be accomplished easily by another party.
6. Power supply redundancy
As a PC server is connected, power supply redundancy was essential. This makes it possible for transfer from the PC server and logging to continue even if the power supply unit malfunctions. Since the entire operational purpose is to store data, even a temporary stoppage has to be avoided.
※3 RAID migration
A function that transfers logic volumes to other RAID groups while performing data verification.
Outputting the contents of files or memory to disk for debugging and data recovery.
Reason for Selecting QNAP: It Seemed Easy to Use
What was the deciding factor in choosing QNAP?
We decided to introduce QNAP after examining a total of three products for these six requirements because QNAP was relatively the best in satisfying our needs.
Apart from these six requirements, QNAP has a refined interface that seemed easy to use.The case and interface design was also quite good and both are extremely important.We decided that since we were satisfied with these we would probably also be satisfied with the functions and reliability.
Members of staff who examined QNAP were also interested. During installation, many of them decided they wanted to watch the startup.
Furthermore, the ability to insert different modules and to add new functions is also interesting.
Were there any uncertainties over reliability?
It is possible to replace a HDD while the QNAP is operating (hot swapping). As hot swapping is impossible without exhaustive reliability testing, it was judged that we could trust the device completely.
In addition, QNAP is also compatible with RAID5 and we thought there would be no problems on this issue either when considering malfunction countermeasures.
This is technology that achieves the following: improved malfunction resistance, higher speed and greater capacity. Parity (error correction code) is distributed and stored on all the disks for memory data recovery in case a disk fails. Data can be rebuilt and recovered quickly in the event of a disk malfunction.
Tell us about your evaluation of QNAP.
Installation was easy, and we completed the setup in a short time. No heavy thinking was necessary and we appreciated being able to put the device into use immediately.
We transfer the data stored on the PC server about once a month. Disk errors have not occurred and we are operating normally. NFS server performance is also good. If compatibility with the NFS client is poor the baud rate may drop and hang-ups might result, but we have not experienced this problem.
When we were operating the PC server only, we could only store about three months' worth of data. Using QNAP, we can store around a year's worth, depending on how it's used.Consequently, we expect that traffic analysis research will probably have great persuasive power.
Future Aspirations and Expectations
Tell us about your future aspirations and expectations.
In future, we would like to use QNAP products as virtual server storage. Compatibility with LDAP (※see Note 6) would broaden the areas of use. We would be delighted if Unity could respond by making some slight changes to the direction to date. Thank you for your cooperation.
Protocols for accessing databases and the uniform handling of information on the network.
Thank you very much for taking time out from your busy schedule today to talk to us.
Date of interview: April 2010