Generic Setup - Avaya 4600 Series Administrator's Manual

4600 Series IP Telephone LAN Administrator's Guide

Generic Setup

Set up of a DHCP server involves the following phases:
1. Install the DHCP server software according to vendor instructions
2. Configure the DHCP server with the following information
IP addresses available for the 4600 Series IP Telephones
Lease duration (Infinite is recommended.)
The following DHCP options:
— Gateway (router) IP address(es) (Table 4-1, item 1). If more than one address is listed,
the total list may contain up to 127 total ASCII characters, with IP addresses
separated by commas with no intervening spaces.
— Subnet mask (Table 4-1, item 3)
— An 4600 Series IP Telephone-specific DHCP option specifying information, such as
TFTP server and DEFINITY CLAN IP addresses. Use the site-specific option (SSON)
at #176. The value for this option should be set to the following string:
MCIPADD=xxx.xxx.xxx.xxx,MCPORT=yyyy,TFTPSRVR=zzz.zzz.zzz.zzz,TFTPDIR=<
path>
Where xxx.xxx.xxx.xxx is one or more IP addresses for DEFINITY CLAN IP boards,
yyyy is the DEFINITY CLAN port (1719), zzz.zzz.zzz.zzz is one or more IP addresses
for TFTP servers, and <path> is the location of the location of the upgrade script and
application files on the TFTP server as entered in Table 4-1, items 4, 5, 2, and 7,
respectively. Each list may contain up to 127 total ASCII characters, with IP addresses
separated by commas with no intervening spaces.
DHCP
4-4
In configurations where the upgrade script and application files are in the
default directory, the TFTPSRVR=zzz.zzz.zzz.zzz setting should not be
used.
Depending on the DHCP application you choose, you should be aware of
the fact that the application most likely will not immediately recycle expired
DHCP leases. An expired lease may remain reserved for the original client
for a day or more (for example, Windows NT DHCP reserves expired
leases for about one day). The intent of this reservation period is to protect
a client's lease in case the client and the DHCP server are in two different
time zones, the computers' clocks are not in synch, or the client is not on
the network when the lease expires.
The implication of this fact may be seen in the following example: Assume
2 IP addresses (hence 2 possible DHCP leases) and 3 IP telephones, two
of which are using the 2 available IP addresses. When the lease expires
for the first two telephones, the third will not be able to get a lease (even if
the other two telephones have been removed from the network), until the
reservation period expires.
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