C-64
Troubleshooting
Diagnostic Tools
DNS Resolver
The Domain Name System (DNS) resolver is designed for use in local network
domains where it enables use of a host name or fully qualified domain name
with DNS-compatible switch CLI commands. (At software release K.13.01, the
DNS-compatible commands include
ping
and
traceroute
.)
Beginning with software release K.13.01, DNS operation supports both IPv4
and IPv6 DNS resolution and multiple, prioritized DNS servers. (For informa-
tion on IPv6 DNS resolution, refer to the latest
IPv6 Configuration Guide
for
your switch.)
Terminology
Domain Suffix —
Includes all labels to the right of the unique host name in
a fully qualified domain name assigned to an IP address. For example, in
the fully qualified domain name “device53.evergreen.trees.org”, the
domain suffix is “evergreen.trees.org”, while “device53” is the unique
(host) name assigned to a specific IP address.
Fully Qualified Domain Name —
The sequence of labels in a domain name
identifying a specific host (host name) and the domain in which it exists.
For example, if a device with an IP address of 10.10.10.101 has a host name
of
device53
and resides in the
evergreen.trees.org
domain, then the
device’s fully qualified domain name is
device53.evergreen.trees.org
and
the DNS resolution of this name is 10.10.10.101.
Host Name —
The unique, leftmost label in a domain name assigned to a
specific IP address in a DNS server configuration. This enables the server to
distinguish a device using that IP address from other devices in the same
domain. For example, in the
evergreen.trees.org
domain, if an IPv4 address
of 10.10.100.27 is assigned a host name of
accounts015
and another IP address
of 10.10.100.33 is assigned a host name of
sales021
, then the switch configured
with the domain suffix
evergreen.trees.org
and a DNS server that resolves
addresses in that domain can use the host names to reach the devices with
DNS-compatible commands. For example:
ping accounts015
traceroute accounts015
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