In the financial, telecommunications billing, aerospace and other fields, relying on clock data provided by the computer itself falls far short of the precise requirement. Causes the time offset of the clock signal is derived from the computer's own simple crystal oscillator, the oscillation frequency of the crystal oscillator is not only related factors shapes, materials, etc. For the cutting direction, but also with factors such as temperature variation, voltage, aging chip, It can not be consistent with the standard frequency of the oscillation frequency, so the time offset occurred.
To eliminate the problem because of the time difference brought about the need for line of equipment, such as database servers, application servers, core network equipment such as time synchronization. Many of the current configuration of the unit is ntp server, high timing accuracy, easy operation, stable performance, good overall effect of the application, provide a favorable time for the industry to achieve network protection era of sophisticated data management.
SYN2136 type Compass NTP network time server
First, when the Internet site ntp service award
Each time the computer is basically inconsistent, which is very important reason is that time of our personal computers are free to modify. In addition to a large number of computer units of network switches, routers also need time to generate a unified log information, unified control. This gives the various departments unified management of data analysis resulted in a series of problems. Faced with this problem, many users consider, there are a lot of vendors on the network time service, free ip address can be used, such as the National Time Service Center site is 210.72.145.44 Microsoft authorized service site is time.windows.com, when there are a lot of educational institutions time service site provided free of charge, simply access the Internet using a computer simply set free these sites be calibrated, it is up to ms accuracy level. That is not the unit there is no need to spend money to purchase ntp server? The answer is in the large number of local area network computer simply can not use this method, the control of others do not know when ip will fail, poor stability, accuracy can not be guaranteed, provided that the additional use of these sites is the need to access the Internet, we are most concerned about security hidden prone to problems. Thus considered, the most practical method of timing or configure a server ntp their own units in the LAN, because time will solve all the problems arising from the fundamental.
Second, ordinary computer can be set to do ntp server
Customers often said that I could be my one piece of equipment computer after the grant as a server for other clients equipment grant, it did not deny the practice, but we all know the configuration and performance of an ordinary computer and a special timing-based server there is a big difference on ordinary computers, servers is a time error accumulated, the greater the deviation over time, generally twelve days there will be error 1-2s. In addition, once a client computer to do this, it would need to shut down for long periods, particularly high configurability also requires, in general, is simply can not be met.
In addition ntp time server is standard utc time is retrieved directly from the satellite, there is no cumulative error, ensure the accuracy of real-time, followed by ntp time source server when the award is due to the accuracy and anti-jamming design specifically for the timing of assurance.
So is not recommended to use an ordinary computer as a server client, a reasonable approach is to choose a real ntp network time server, say now Xi'an ntp network time server to synchronize rich product type, price close to the people, fully meet the different units of the grant demand.
SYN2136 type Compass NTP network time server
Third, the time difference is too large ntp time server can not synchronize
Some customers actually use them for testing purposes directly to the adjustment of the local time and standard time difference is too large, then even if the client and the ntp server configuration is correct may also be a matter of time can not be out of sync, below us We will discuss why there is such a problem, how to solve if you encounter this?
First we start with the ntp protocol, for security reasons, ntp protocol, there are provisions in this regard. Not more than a certain time difference can not be synchronized, but as an option, the client is fully configurable. That all operating systems ntp has run, it can limit the maximum time error between the client and the ntp server. How to set the maximum error of time, depending on the importance of the client's time, if the range is not important to set a general time error is relatively large, especially important if, like banking financial sector is relatively high for the time, the range of error of time must Juin is relatively small, usually a few minutes. Moreover, some computer bios time and system time once the difference over 30 minutes, it will immediately report the above error, then simply modify the bios or system time to time.
Unless it exceeds the set range can be a normal correction In summary, the time error between the client and the server ntp exist. Once the time difference is too large can not synchronize ntp time server error, we first need to rule out is whether the client's time we set for the purpose of debugging time and normal time apart too much, followed by a clock out of order. At this point do not recommend automatically correct, this may result in business risk, it is recommended immediately to manually check the client time and date settings correctly.
SYN2136 type Compass NTP network time server
Four, ntp server to use
NTP NTP server is generally a time for the interface can only give the same network segment where the device right. After receiving the first device to the computer and we can ntp servers and direct-attached, do a simple test. For devices directly connected to the case of the PC, the PC must give your computer a static setting, with a network IP address of a different IP. Then in the bottom right corner of the computer's time to modify Internet settings inside ip address, we will modify the ntp server ip ip can be successful synchronization.
And all the preparation work, we can ntp server to the LAN, connecting the core switch, a device management ip in the web management page, be noted that the award of the corresponding interface of the device and ntp server ip ip need the same through a network can fight with each other.
Synchronization ntp servers are fool-operation concept, using the operation are relatively simple, just control instructions can get their own.
Here it should be noted that, in practical applications, ntp server is a computer and network equipment like normal, normal network originally isolated network segment, networking support inter-network access if another device, then we ntp server also supports. Otherwise, it and the next switch, two computers set up different network segments, is no way to normal communications. So you need a user in the procurement and staff make it clear that we need a few road ntp output, the need to meet several physical devices grant an isolated network, to avoid unnecessary problems later.
