allow-dns-reply

Syntax

Hierarchy Level

Release Information

Statement introduced in Release 8.5 of Junos OS.

Description

Allow an incoming Domain Name Service (DNS) reply packet without a matched request. By default, if an incoming UDP first-packet has dst-port 53, the device checks the DNS message packet header to verify that the query bit (QR) is 0, which denotes a query message. If the QR bit is 1, which denotes a response message, the device drops the packet, does not create a session, and increments the illegal packet flow counter for the interface. Using the allow-dns-reply statement directs the device to skip the check.

Usage Guidelines

For configuration instructions and examples, see the Junos OS Security Configuration Guide.

Required Privilege Level

security—To view this statement in the configuration.

security-control—To add this statement to the configuration.