By default, the NIOS appliance responds to DNS queries from any IP address. You can create a list of queriers to which the appliance is allowed to respond; restricting it to specific networks, IP addresses, and remote servers that present specified TSIG (transaction signature) keys. When using TSIG keys, it is important that the appliances and servers involved with the authentication procedure use NTP (Network Time Protocol) for their time settings (see Using NTP for Time Settings).
In addition, you can also configure the appliance to respond to recursive queries. A recursive query requires the appliance to return requested DNS data, or locate the data through queries to other servers. Recursion is disabled by default. If you enable this feature, you can also create a list of allowed recursive queries. For information about allowing recursion, refer to to Enabling Recursive Queries.
You can create a list of allowed queriers for the Grid and for individual Grid members.

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Specifying Queries

To configure a list of allowed queriers for the Grid or for a member:

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