H3C MSR 2600 Series, Configuration Manual

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Tasks at a glance
(Optional.) Configuring the DNS trusted interface
(Optional.) Specifying the DSCP value for outgoing DNS packets
Configuring the IPv4 DNS client
Configuring static domain name resolution
Static domain name resolution allows applications such as Telnet to contact hosts by using host names
instead of IPv4 addresses.
Follow these guidelines when you configure static domain name resolution:
•
On the public network or a VPN, each host name maps to only one IPv4 address. The most recent
configuration for a host name takes effect.
•
You can configure host name-to-IPv4 address mappings for the public network and up to 1024
VPNs, and configure a maximum of 1024 host name-to-IPv4 address mappings for the public
network or each VPN.
To configure static domain name resolution:
Step Command Remarks
1. Enter system view.
system-view N/A
2. Configure a mapping between a
host name and an IPv4 address.
ip host host-name ip-address
[ vpn-instance vpn-instance-name ]
By default, no mapping
between a host name and
an IPv4 address is
configured.
Configuring dynamic domain name resolution
To use dynamic domain name resolution, configure DNS servers so that DNS queries can be sent to a
correct server for resolution. A DNS server manually configured takes precedence over the one
dynamically obtained through DHCP, and a DNS server configured earlier takes precedence. A name
query is first sent to the DNS server that has the highest priority. If no reply is received, it is sent to the DNS
server that has the second highest priority, and thus in turn.
In addition, you can configure a DNS suffix that the system automatically adds to the provided domain
name for resolution. A DNS suffix manually configured takes precedence over the one dynamically
obtained through DHCP, and a DNS suffix configured earlier takes precedence. The DNS resolver first
uses the suffix that has the highest priority. If the name resolution fails, the DNS resolver uses the suffix that
has the second highest priority, and thus in turn.
Configuration guidelines
Follow these guidelines when you configure dynamic domain name resolution:
•
You can specify DNS server IPv4 addresses for the public network and up to 1024 VPNs, and
specify a maximum of six DNS server IPv4 addresses for the public network or each VPN.