While something is wrong with the master device, the slave device can replace it quickly. Using standby technology will make service of communication network do not halt in a long time.

当主设备出现故障时，从设备迅速地接替它进行工作，这样就可以确保网络通讯不出现长时间的中断。

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Once there is something wrong with the active equipment, the standby one can replace it immediately to continue working, in this way the communication network will not be interrupted for a long time.

当主设备出现故障时，从设备迅速地接替它进行工作，这样就可以确保网络通讯不出现长时间的中断。

youdao

This essential piece of documentation will not replace the real thing, but many users said having it handy can save time in emergency situations.

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