diff --git a/test/shell/writecache.sh b/test/shell/writecache.sh
index ce77cfeff..42c864a9b 100644
--- a/test/shell/writecache.sh
+++ b/test/shell/writecache.sh
@@ -48,7 +48,7 @@ cp pattern1 $mount_dir/pattern1
 umount $mount_dir
 lvchange -an $vg/$lv1
 
-lvconvert --type writecache --cachepool $lv2 $vg/$lv1
+lvconvert --yes --type writecache --cachepool $lv2 $vg/$lv1
 
 check lv_field $vg/$lv1 segtype writecache
 
@@ -90,7 +90,7 @@ lvchange -an $vg/$lv2
 
 # test2: create fs on LV after writecache is attached
 
-lvconvert --type writecache --cachepool $lv2 $vg/$lv1
+lvconvert --yes --type writecache --cachepool $lv2 $vg/$lv1
 
 check lv_field $vg/$lv1 segtype writecache
 
diff --git a/tools/lvconvert.c b/tools/lvconvert.c
index 3ba7f5b02..2c6384e76 100644
--- a/tools/lvconvert.c
+++ b/tools/lvconvert.c
@@ -5498,6 +5498,12 @@ static int _lvconvert_writecache_attach_single(struct cmd_context *cmd,
 		return 0;
 	}
 
+	if (!arg_is_set(cmd, yes_ARG) &&
+	    yes_no_prompt("Erase all existing data on %s? [y/n]: ", display_lvname(lv_fast)) == 'n') {
+		log_error("Conversion aborted.");
+		return 0;
+	}
+
 	/* Ensure the two LVs are not active elsewhere. */
 	if (!lockd_lv(cmd, lv, "ex", 0))
 		goto_bad;