Specifying the source interface for DNS packets
By default, the device uses the primary IP address of the output interface of the matching route as the source IP address of a DNS request. Therefore, the source IP address of the DNS packets may vary with DNS servers. In some scenarios, the DNS server only responds to DNS requests sourced from a specific IP address. In such cases, you must specify the source interface for the DNS packets so that the device can always use the primary IP address of the specified source interface as the source IP address of DNS packets.
To specify the source interface for DNS packets:
Step | Command | Remarks |
|---|---|---|
1. Enter system view. | system-view | N/A |
2. Set the DSCP value for DNS packets. | dns source-interface interface-type interface-number | By default, no source interface for DNS packets is specified. The device uses the primary IP address of the output interface of the matching route as the source IP address of a DNS request. |