Possible aproach for MySQL replication This might be a duplicate questions asked before. But I need to understand a possible approach for my ENV running innodb engine.
Is it possible to upgrade a Master MySQL Server to 5.5 to 5.6 and  replication Slave which is on Version 5.7

If this is possible then how do we perform this activity, because we am getting this below error of Server_UUID when replicating the Slave (Slave version 5.7.11 and Master Version 5.6.29)

Errno: 1593
Fatal error: The slave I/O thread stops because master and slave
have equal MySQL server UUIDs; these UUIDs must be different for
replication to work.


Purpose is to UPGRADE both the server on the same version 5.7

Currently Version   

Server1 and Server2 are on 5.6.29   

Beginner in MySQL unable to understand the concept of replication with the new version, open for better suggestion.
Check out this article by the folks at Percona regarding duplicate UUIDs, it may be worth checking how the slave was created originally and checking out the auto.cnf settings on each server.
https://www.percona.com/blog/2014/01/21/beware-mysql-5-6-server-uuid-cloning-slaves/