Bug #90217 Add IPv6 support for Group Replication
Submitted: 26 Mar 2018 15:07 Modified: 8 Jan 2019 15:13
Reporter: Artem Danilov Email Updates:
Status: Closed Impact on me:
None 
Category:MySQL Server: Group Replication Severity:S1 (Critical)
Version:8.0 OS:Any
Assigned to: CPU Architecture:Any

[26 Mar 2018 15:07] Artem Danilov 
Description:
The documentation https://dev.mysql.com/doc/refman/8.0/en/group-replication-requirements.html says:
 
"IPv4 Network.  The group communication engine used by MySQL Group Replication only supports IPv4. Therefore, Group Replication requires an IPv4 network infrastructure."

This is a very critical problem for the companies which completely moved to IPv6.

How to repeat:
The documentation makes it clear that IPv4 is not supported: https://dev.mysql.com/doc/refman/8.0/en/group-replication-requirements.html
[26 Mar 2018 15:42] Kumar Verma 
Verified via documentation :
Pre-General Availability Draft: 2018-03-23

21.7.1 Group Replication Requirements
IPv4 Network.  The group communication engine used by MySQL Group Replication only supports IPv4. Therefore, Group Replication requires an IPv4 network infrastructure.
[8 Jan 2019 15:13] Margaret Fisher 
Posted by developer:
 
Implemented as WL #11926 in MySQL 8.0.14. Changelog entry:

        The Group Communication System (GCS) and group communication
        engine (XCom, a Paxos variant) for Group Replication now provide
        full support for IPv6, so replication group members can use IPv6
        addresses as an alternative to IPv4 addresses for internal group
        communications. The localhost address for IPv6, and the private
        subnetwork addresses for IPv6 (unique-local addresses and
        link-local unicast addresses), are added to the automatic
        whitelist for Group Replication for use if no manual whitelist
        is specified.

        If all members of a replication group are at a MySQL server
        version that supports the use of IPv6 addresses for Group
        Replication, the group can contain a mix of members using IPv6
        addresses and members using IPv4 addresses. Joining members must
        provide whitelisted IP addresses or host names that match the
        protocols offered by the seed members for connection, but the
        joining member's main identifying address or host name
        (group_replication_local_address)
        can use either protocol. If a member uses a host name that
        resolves to both an IPv4 and an IPv6 address, the IPv4 address
        is always used for Group Replication connections.

        If any or all existing members of a replication group are using
        an older MySQL Server version without support for the use of
        IPv6 addresses for Group Replication, joining members must
        present an IPv4 address for group communications in the
        group_replication_local_address
        option. When every group member has been upgraded, the group can
        be migrated to IPv6 addresses.