How automatic configuration works
Automatic configuration works in the following manner:
1.During startup, the device sets the first up interface (if up Layer 2 Ethernet interfaces are available, the VLAN interface of the default VLAN of the Ethernet interfaces is selected as the first up interface.) as the DHCP client to request parameters from the DHCP server, such as an IP address and name of a TFTP server, IP address of a DNS server, and the configuration file name.
2.After getting related parameters, the device sends a TFTP request to obtain the configuration file from the specified TFTP server and executes the configuration file. If the client cannot get such parameters, it uses factory default configuration.
NOTE:
•To implement automatic configuration, you need to configure the DHCP server, DNS server and TFTP server, but you do not need to perform any configuration on the device that performs automatic configuration.
•Before starting the device, connect only the interface needed in automatic configuration to the network.
Work flow of automatic configuration
Figure 50 shows the work flow of automatic configuration.
Figure 50 Work flow of automatic configuration
Start the device with default configuration
The interface obtains parameters through DHCP
Yes
Is the TFTP server address contained in the parameters?
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| Fails | Unicast a TFTP request to |
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| obtain the configuration file |
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Remove the temporary |
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configurations and the device |
| configurations and execute |
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starts with default configuration |
| the obtained configuration file |
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| End |
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| starts with default configuration |
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