# \[PATCH\] Grow: analyse\_change add notification about only 2-device can be convert from RAID1 to RAID5

- From: Yi Zhang \<hidden\>
- Date: 2016-03-11 09:26:40 
- List: linux-raid
- Page: https://ratatoskr.run/linux-raid/2016/03/6631757
- Thread: https://ratatoskr.run/linux-raid/2016/03/6631757/t.md

```text
Notify "Can only convert a 2-device array to RAID5" instead of
"Impossibly level change request for RAID1" when convert from
RAID1 to RAID5 if the disk num is not equal two like RAID4/5->RAID1
did.

Signed-off-by: Yi Zhang <redacted>
---
 Grow.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Grow.c b/Grow.c
index cf2750a..4e2fc08 100755
--- a/Grow.c
+++ b/Grow.c
@@ -1077,6 +1077,9 @@ char *analyse_change(char *devname, struct mdinfo *info, struct reshape *re)
 			re->level = 1;
 			return NULL;
 		}
+		if (info->array.raid_disks != 2 &&
+		    info->new_level == 5)
+			return "Can only convert a 2-device array to RAID5";
 		if (info->array.raid_disks == 2 &&
 		    info->new_level == 5) {
 
-- 
2.5.0

```