Avaya 4600 Series Administrator's Manual page 55

- Option 6 - DNS server(s) address list. If using more than one address, the total list can
contain up to 127 total ASCII characters. You must separate IP Addresses with
commas with no intervening spaces. At least one address in Option 6 must be a valid,
non zero, dotted decimal address. Otherwise, DNS will fail.
- Option 15 - DNS Domain Name. This string contains the domain name to be used
when DNS names in system parameters are resolved into IP Addresses. This domain
name is appended to the DNS name before the 4600 IP Telephone attempts to resolve
the DNS address. Option 15 is necessary if you want to use a DNS name for the TFTP
server. Otherwise, you can specify a DOMAIN as part of customizing TFTP as
indicated in
- Option 51 - DHCP lease time, if desired. We recommend six weeks or greater. Expired
leases cause Avaya IP Telephones to reboot. It is highly desirable to provide enough
leases so an IP telephone's IP Address does not change if it is briefly taken offline.
Note:
The DHCP standard states that when a DHCP lease expires, the device should
Note:
immediately cease using its assigned IP Address. This is not necessarily the
desired behavior for telephones, especially if a user is on a call. If the network
has problems and the only DHCP server is centralized, the server is not
accessible to the given telephone. In this case the telephone is not usable until
the server can be reached.
Preferably, once assigned an IP Address, the telephone continues using that
address after the DHCP lease expires, until a conflict with another device is
detected. As
Parameters
administrator to specify that the telephone will either:
- Comply with the DHCP standard by setting DHCPSTD to "1", or
- Continue to use its IP Address after the DHCP lease expires by setting DHCPSTD
to "0."
The latter case is the default. If the default is invoked, after the DHCP lease expires
the telephone sends an ARP Request for its own IP Address every five seconds.
The request continues either forever, or until the phone receives an ARP Reply.
After receiving an ARP Reply, the telephone displays an error message, sets its IP
Address to 0.0.0.0, and attempts to contact the DHCP server again.
- Option 52 - Overload Option, if desired. If this option is received in a message, the
telephone interprets the sname and file fields in accordance with RFC 2132,
Section 9.3.
- Option 58 - DHCP lease renew time, if desired.
- Option 59 - DHCP lease rebind time, if desired.
- Option 66 - TFTP Server Name, applicable to H.323 only.
DNS Addressing on page 94.
Table 6: 4600 Series IP Telephone Customizable System
on page 86 indicates, the system parameter DHCPSTD allows an
Issue 2.3 November 2005
DHCP
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