Dynamic Dns Link Does Not Work In The Dhcp Functionality - Alaxala AX6700S series Troubleshooting Manual

3.7.3 Dynamic DNS link does not work in the DHCP functionality

(1) Communication problems on the DHCP server
There are three probable causes for communication problems on a DHCP server:
1. A configuration is set incorrectly.
2. The network configuration is changed.
3. The DHCP server fails.
First, check for cause 1. Described below are likely examples of incorrect configuration. For cause
2, check the differences in the network configuration before and after the change to uncover any
cause that could disable communication. You might have checked the settings of the DNS server
and DHCP server (such as network card settings and cable connections) and concluded that cause
3 applies. For example, the configuration and network configuration are correct, but the Dynamic
DNS link does not work. In such a case, see (b)Checking the time information through (f)Checking
the filters and QoS configuration information for details.
Use the following flowchart to isolate the fault location to identify the cause of the problem.
Figure 3-9: Failure analysis procedure on the DHCP server when DNS is linked
(a) Checking the configuration
The probable cause is that DNS updating is not working properly for Dynamic DNS because some
settings on the DHCP server are incorrect or not consistent with the settings on the DNS server. To
check the configuration, do the following:
1. First, check the method for permitting DNS updating on the DNS server. For access
permission based on IP addresses and networks, see the items 3 onwards. For permission
based on authentication keys, see the items 2 onwards.
3. Troubleshooting Functional Failures During Operation
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