Allied Telesis AT-iMG634 - R2 User's Guide Page 544

  • Download
  • Add to my manuals
  • Print
  • Page
    / 998
  • Table of contents
  • BOOKMARKS
  • Rated. / 5. Based on customer reviews
Page view 543
Domain name system - DNS DNS Relay
iMG/RG Software Reference Manual (System Administration)
5-84
5.2.1 DNS Relay
gateway can act as a DNS relay. So, DNS packets that arrive at the Residential Gateway, addressed to the Resi-
dential Gateway, will be relayed on to a known DNS Server.
In this way, devices on the LAN can treat the Residential Gateway as though it were the DNS Server. Only the
Residential Gateway needs to know the address of the real DNS Server looking into it is internal DNS Relay
servers list.
It's possible configure the DHCP server running on the internal Residential Gateway's IP interface in order to
offer the IP address of it's internal IP interface as DNS server's IP address for the internal hosts DNS requests.
It's also possible write a file named dnsrelaylandb with information about host attributes and a domain name
and IP address mask. When DNS relay will receive a DNS request it will check if the answer to this request is
in this file and in this case it will answer to the question; if it hasn’t enough information it will forward the
request to a DNS server.
It is possible to nominate both a primary and a secondary DNS server to contact. DNS responses received
from the server are then forwarded back to the original host making the DHCP request.
Both UDP and TCP DNS requests are supported.
The DNS relay does not bind itself to any one specific interface or interface type, but rather will listen for traf-
fic on all available IP interfaces. It relies on the well known UDP and TCP port number for a DNS server (port
number 53) for receiving DNS traffic.
5.2.2 DNS Client
The ggatewayateway is provided with an internal DNS client, to use this function you must add DNS server
addresses that will be used by the Residential Gateway ONLY for its own lookups.
5.2.3 DNS Relay command reference
This section describes the commands available on the gateway to enable, configure and manage the DNS Relay
module.
5.2.3.1 DNS Relay CLI commands
The table below lists the DNSrelay commands provided by the CLI:
Page view 543
1 2 ... 539 540 541 542 543 544 545 546 547 548 549 ... 997 998

Comments to this Manuals

No comments