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Configuring the DNS server
A DNS server is required in the following situations:
•
The TFTP server does not have a host name file. However, devices need to perform the
following operations:
Use their IP addresses to obtain their host names.
Obtain configuration files named in the
host name.cfg
format from the TFTP server.
•
The DHCP server assigns the TFTP server domain name through the DHCP reply message.
Devices must use the domain name to obtain the IP address of the TFTP server.
Configuring the gateway
If the devices to be automatically configured and the servers for automatic configuration reside in
different network segments, you must perform the following tasks:
•
Deploy a gateway and make sure the devices can communicate with the servers.
•
Configure the DHCP relay agent feature on the gateway.
•
Configure the UDP helper feature on the gateway.
When a device sends a request through a broadcast packet to the file server, the UDP helper
changes the broadcast packet to a unicast packet and forwards the unicast packet to the file
server. For more information about UDP helper, see
Layer 3—IP Services Configuration Guide
.
Preparing the interface used for automatic configuration
The device uses the following steps to select the interface for automatic configuration:
1.
Identifies the status of the management Ethernet interface at Layer 2. If the status is up, the
device uses the management Ethernet interface.
2.
Identifies the status of Layer 2 Ethernet interfaces. If one or more Layer 2 Ethernet interfaces
are in up state, the device uses the VLAN interface of the default VLAN.
3.
Sorts all Layer 3 Ethernet interfaces in up state first in lexicographical order of interface types
and then in ascending order of interface numbers. Uses the interface with the smallest interface
number among the interfaces of the first interface type.
4.
If no Layer 3 Ethernet interfaces are in up state, the device waits 30 seconds and goes to step
1 to try again.
For fast automatic device configuration, connect only the management Ethernet interface on each
device to the network.
Starting and completing automatic configuration
1.
Power on the devices to be automatically configured.
If a device does not find a next-start configuration file locally, it starts the automatic
configuration process to obtain a configuration file. If one attempt fails, the device waits 30
seconds and then automatically starts the process again. To stop the process, press
Ctrl+C
or
Ctrl+D
.
After obtaining a configuration file, the device automatically executes the configuration file.
2.
Use the
save
command to save the running configuration.
The device does not save the obtained configuration file locally. If you do not save the running
configuration, the device must use the automatic configuration feature again after a reboot.
Summary of Contents for FlexNetwork 10500 Series
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