Here are the answers

1) keystone URL is http://DEVSTACK-MACHINE-IP:5000/v2.0/

2) In the localrc, add this entry HOST_IP=IP OF DEVSTACK-MACHINE.

With this change, the rest endpoints will be based on IP instead of localhost

3) You can create a tenant by using horizon UI. Login using the user "admin" and password set by you either in localrc or while running stack.sh

If you want to create using Keystone CLI, then do the following

cd devstack

source openrc admin admin

keystone tenant-create

To know what are the exact parameters to pass, you can use "help" as mentioned below

sagar@sagar-eclipse:~/devstack$ keystone help tenant-create

usage: keystone tenant-create --name <tenant-name> [--description <tenant-description>] [--enabled <true|false>]

Create new tenant

Optional arguments: --name <tenant-name> New tenant name (must be unique) --description <tenant-description> Description of new tenant (default is none) --enabled <true|false> Initial tenant enabled status (default true)