Index: uspace/srv/bd/hr/raid0.c
===================================================================
--- uspace/srv/bd/hr/raid0.c	(revision 5f543e9186ef3f5ceb3c24f016bc226aaa9fe496)
+++ uspace/srv/bd/hr/raid0.c	(revision 182ffcc2cc90bf2094406e6305862139066c8519)
@@ -160,4 +160,7 @@
 			rc = block_sync_cache(vol->extents[extent].svc_id,
 			    phys_block, cnt);
+			/* allow unsupported sync */
+			if (rc == ENOTSUP)
+				rc = EOK;
 			break;
 		case HR_BD_READ:
Index: uspace/srv/bd/hr/raid1.c
===================================================================
--- uspace/srv/bd/hr/raid1.c	(revision 5f543e9186ef3f5ceb3c24f016bc226aaa9fe496)
+++ uspace/srv/bd/hr/raid1.c	(revision 182ffcc2cc90bf2094406e6305862139066c8519)
@@ -177,5 +177,5 @@
 				continue;
 			rc = block_sync_cache(vol->extents[i].svc_id, ba, cnt);
-			if (rc != EOK)
+			if (rc != EOK && rc != ENOTSUP)
 				handle_extent_error(vol, i, rc);
 			else