<div dir="ltr"><div class="gmail_default" style="font-family:monospace,monospace">Hi guys,</div><div class="gmail_default" style="font-family:monospace,monospace"><br></div><div class="gmail_default" style="font-family:monospace,monospace">my scenario is the following:</div><div class="gmail_default" style="font-family:monospace,monospace">- several 4.2 Authoritative servers</div><div class="gmail_default" style="font-family:monospace,monospace">-  multi-master database configuration (Percona XtraDB Cluster for instance) </div><div class="gmail_default" style="font-family:monospace,monospace"><br></div><div class="gmail_default" style="font-family:monospace,monospace">In order to upgrade to 4.3 and avoid downtime, is it safe to upgrade the database schema first and every server then?</div><div class="gmail_default" style="font-family:monospace,monospace"><br></div><div class="gmail_default" style="font-family:monospace,monospace">Thanks a lot</div><div class="gmail_default" style="font-family:monospace,monospace"><br></div></div>