IPv6 and Domino
You can enable IPv6 support in IBM® Domino® for SMTP, POP3, IMAP, LDAP, and HTTP services on IBM AIX®, IBM i, and Linux™ systems.
Domino supports both IPv6
and IPv4. Thus, if an IPv6-enabled Domino server
encounters an IP address in IPv4 format, the Domino server can still make the connection
to that address. When attempting to connect to a server, Domino tries to resolve all IP addresses for
a server until one works. This allows a server to have both an IPv4
address and an IPv6 address. Domino caches
the last successful address for a server and uses only the cached
address to quickly search for a server. If you do not want to use
only the cached address, enter the NOTES.INI setting DONT_USE_REMEMBERED_ADDRESSES=1
.
In DNS, records that store IPv6 addresses are called AAAA records. After you enable IPv6 on a Domino server and add the server's AAAA record to DNS, another IPv6-enabled Domino server can connect to it only over IPv6. Servers that don't support IPv6 can run Domino with IPv6 support disabled, which is the default. These servers can successfully connect to IPv6-enabled Domino servers only if the DNS for the IPv6 servers contain A records.
Using IPv6 in a Domino network
For best results when using IPv6 with Domino servers, set up network devices in the network pathway to connect directly with native IPv6, rather than tunnel through the IPv4 network.
Enabling IPv6 on Notes® and Domino
To enable IPv6
on Notes and Domino, add the
setting TCP_ENABLEIPV6=1
to the NOTES.INI file
on both the Notes client
and the Domino server.
How Domino decides whether to connect over IPv6 or IPv4
A Domino server evaluates the address format and then, based on that information, makes an IPv4 or an IPv6 connection.
Address format |
Server response |
---|---|
IPv4 |
Makes an IPv4 connection. |
IPv4 address mapped to IPv6 |
Attempts to make an IPv6 connection and waits for the TCP/IP software to make either an IPv6 or IPv4 connection, depending on the remote system's TCP/IP stack. |
IPv6 |
Makes an IPv6 connection. |
Server name |
Uses DNS to resolve the name:
|