dns snooping server-ip-address
Function
The dns snooping server-ip-address command configures the IP address of a DNS server.
The undo dns snooping server-ip-address command deletes the configuration of a DNS server IP address.
By default, no DNS server IP address is configured on the device.
This command is supported only by the S5720-HI, S5730-HI, S5731-H, S5731S-H, S6720-HI, S5732-H, S6730-H, S6730S-H, and S6730S-HI.
Format
dns snooping server-ip-address server-ip-address
undo dns snooping server-ip-address server-ip-address
Parameters
| Parameter | Description | Value |
|---|---|---|
server-ip-address |
Specifies the IP address of a DNS server. |
The value is in dotted decimal notation. |
Usage Guidelines
After DNS snooping is enabled, the device parses the received DNS response packets to obtain IP addresses and generates mappings between the IP addresses and domain names. To prevent attacks initiated by DNS response packets, you can run the dns snooping server-ip-address command to specify the IP address of a DNS server. The device then processes only the DNS response packets with the configured DNS server IP address as the source IP address.