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Order of operations for dns on the switch, Order of operations for dns on the switch -5 – Avaya 580 User Manual

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Document No. 10-300077, Issue 2

11-5

Configuring DNS Client

Order of Operations for DNS on the Switch

You can configure up to six DNS servers and up to six DNS suffixes. When
you use a name instead of an IP address in a command, the Avaya
Multiservice switch will first check to see if the name is a fully qualified
domain name (ex: hostA.avaya.com). If it is, this will be sent to the first
DNS server in the list of servers.

If it is not a fully qualified domain name (ex: just hostA) and a suffix(es)
has been specified, the first suffix will be appended to the name; and then
sent to the DNS server. If no suffix(es) is configured, it will be sent as is for
resolution.

If the server cannot resolve the name, the Avaya Multiservice switch will
use the same method with the second configured suffix. Once it has
exhausted the configured DNS suffixes, it will attempt the query with the
second DNS server.

This process will continue until the name is either resolved, there are no
more DNS servers in the list, or the DNS server returns an error.

Table 11-1

lists the error messages and their meanings that you may encounter when
using the DNS client.

Table 11-1. DNS Error Codes

Error Message

Explanation

Bad ARGS

indicates that DNS is Disabled but the user entered a host name.

Name Too Long

the name sent is too long. RFC 1034 limits DNS names to
255 characters.

Bad Name

indicates that the name was in some way invalid

Label Too Long

indicates that the label of a DNS name was too long. RFC 1034
limits labels to 63 octets.

Time-out

indicates that the DNS query has expired. This implies that the
query could not be answered at the present time.

Server Failure

indicates that the DNS server is unable to answer due to a failure
on the DNS server itself.

Non-Existent Name

indicates that the DNS server authoritatively claims that the DNS
name does not exist.

NIY

Indicates the DNS server does not support the requested service.
You may have specified the correct DNS server but the server
has not yet been configured to respond to DNS queries.

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