thanks larsks and dbaxps

I checked my nova config file config_drive was set

"force_config_drive=always"

and i had this cnould init file (actually i tried many cloud init files)

cat myconfig.txt :-

#cloud-config
chpasswd:
 list: |
   root:stackops
   centos:stackops
 expire: False

cat mynewconfig.txt

#cloud-config users: - name: demo passwd: $6$rounds=4096$X3xB1mwI$K0tjjjGmQd2HeC4PH2lqEM8MT5JCupvtx6RyXoCvUwZOnhhfJaVXjddkM03bVXmSDbb9CtrpOVykJFsj1OsDD/

chpasswd: list: | root:stackops centos:stackops expire: False

ssh_pwauth: True

runcmd: - [ ls, -l, / ] - [ sh, -c, echo "=========hello world'=========" ]

and i am creating the vm using

server = nova.servers.create(name = vmName, image = image.id, flavor = flavor.id, nics = nicss, availability_zone = availability_zone , userdata = user_data, key_name = key_pair.name )

but nothing worked!

but dbaxps .. i tried your solution it worked.

Do you mind explaining ( for understanding what i might be doing wrong) .. was i using the wrong format "passwd" ?? or is it the combination that was wrong ? means i tried password , ssh_pwauth, choasswd everythign .. but may be not right combination like

passwd password: mysecret , chpasswd: { expire: False }, ssh_pwauth: True