node specificatino with --oss and --mds doesn't work

[sihara]

# ./lod -d --node ec01 --oss ec01 --mds ec01 --mdtdevs=/dev/sda --ostdevs=/dev/sdb --fsname=a --mountpoint=/mnt/lustre initialize
[2020/08/25-17:54:09] [ERROR] [lod.py:195] mds_list not contained in node_list, ec01/['ec01'].
[2020/08/25-17:54:09] [ERROR] [lod.py:1051] invalid lod options, please correct it.
['-d', '--node', 'ec01', '--oss', 'ec01', '--mds', 'ec01', '--mdtdevs=/dev/sda', '--ostdevs=/dev/sdb', '--fsname=a', '--mountpoint=/mnt/lustre', 'initialize']

without --oss and --mds, it seems to be working

# ./lod -d --node ec01 --mdtdevs=/dev/sda --ostdevs=/dev/sdb --fsname=a --mountpoint=/mnt/lustre initialize
Operator: initialize
MDS: ['ec01']
	       mgs: /tmp/.lod_mgt_200M	---> ec01
	      mdt0: /dev/sda	---> ec01
OSS: ['ec01']
	      ost0: /dev/sdb	---> ec01
Clients:
	ec01	/mnt/lustre
Fsname: a
Net: tcp
Mountpoint: /mnt/lustre