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The value of this system variable cannot be changed while Group Replication is running. 

group_replication_group_name  specifies the name of the group which this server instance belongs to, which must be a valid UUID. This UUID forms part of the GTIDs that are used when transactions received by group members from clients, and view change events that are generated internally by the group members, are written to the binary log. 

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• group_replication_group_seeds 

## Important 

A unique UUID must be used. 

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The value of this system variable can be changed while Group Replication is running, but the change only takes effect after you stop and restart Group Replication on the group member. 

group_replication_group_seeds  is a list of group members to which a joining member can connect to obtain details of all the current group members. The joining member uses these details to select and connect to a group member to obtain the data needed for synchrony with the group. The list consists of a single internal network address or host name for each included seed member, as configured in the seed member’s group_replication_local_address  system variable (not the seed member’s SQL client connection, as specified by MySQL Server’s hostname  and port  system variables). The addresses of the seed members are specified as a comma separated list, such as host1:port1 , host2:port2 . An IPv6 address must be specified in square brackets. For example: 

group_replication_group_seeds= 

Note that the value you specify for this variable is not validated until a START GROUP_REPLICATION statement is issued and the Group Communication System (GCS) is available. 

Usually this list consists of all members of the group, but you can choose a subset of the group members to be seeds. The list must contain at least one valid member address. Each address is validated when starting Group Replication. If the list does not contain any valid member addresses, issuing START GROUP_REPLICATION  fails. 

When a server is joining a replication group, it attempts to connect to the first seed member listed in its group_replication_group_seeds  system variable. If the connection is refused, the joining member tries to connect to each of the other seed members in the list in order. If the joining member connects to a seed member but does not get added to the replication group as a result (for example, because the seed member does not have the joining member’s address in its allowlist and closes the connection), the joining member continues to try the remaining seed members in the list in order. 

A joining member must communicate with the seed member using the same protocol (IPv4 or IPv6) that the seed member advertises in the group_replication_group_seeds  option. For the purpose 

