If IPv4-only operation is enabled, the system ignores any IPv6 addresses configured as parameter
values and uses the next IPv4 address in the list. If the parameter value does not contain any IPv4
addresses, the system treats the value as null.
If IPv6-only operation is enabled, any IPv4 addresses configured as parameter values are ignored,
and the next IPv6 address (if any) in a list of addresses is used. If the parameter value does not
contain any IPv6 addresses, the system treats the value as null.
The results of the determination are expressed in the following table.
Table 8: IP Enablement Results
Manually
program-
med IPv4
address?
IPV6STAT
Manually
programmed
IPv6 address
DHCPSTAT
Result
Addressing Mode(s)
IPv4
IPv6
No
0
N/A
n/a
IPv4 only
DHCP
n/a
1
No
Yes
1
2
3
1 or 3
2
IPv4 only
IPv6 only
dual-stack
dual-stack
IPv6 only
DHCP
n/a
DHCP
DHCP
n/a
n/a
DHCPv6
DHCPv6
manual
manual
Yes
0
n/a
n/a
IPv4 only
manual
n/a
1
No
Yes
1
2 or 3
n/a
IPv4 only
dual-stack
dual-stack
manual
manual
manual
n/a
DHCPv6
manual
In general, if dual-stack operation is enabled, whether IPv4 or IPv6 is to be used to contact a
server is determined by the value of the parameter that contains the server address(es). However,
if the value is a DNS name and if DNS returns both an IPv4 and an IPv6 address, the one that will
be used is controlled by the parameter IPPREF.
Related links
on page 82
Features not supporting IPv6
The features and capabilities detailed in the following table are not available with IPv6 in H.323
software Release 6.0 or later:
Server Administration
May 2018
Installing and Administering Avaya J169/J179 IP Phone H.323
95