func (wr *Wrangler) checkMasterElect(ti *topo.TabletInfo) error { // Check the master-elect is fit for duty - call out for hardware checks. // if the server was already serving live traffic, it's probably good if ti.IsInServingGraph() { return nil } return wr.ExecuteOptionalTabletInfoHook(ti, hook.NewSimpleHook("preflight_serving_type")) }