Throttle disk write to prevent etcd puking during upgrade

clitools/pkg/node/uboot/ab.go

@@ -32,7 +32,7 @@ func ConfigureABBoot(ctx context.Context, nctx *node.NodeContext) error {
 				return fmt.Errorf("read boot state: %w", err)
 			}
 
-			bootPart := state["BOOT_PART"]
+			bootPart = state["BOOT_PART"]
 			if bootPart == "" {
 				return fmt.Errorf("BOOT_PART missing")
 			}