just use a combined solution with properly setup ssh_config + resolv.conf:
1 . setup /etc/resolv.conf
search my_cool_domain.com
2 . setup your ssh_config for mapping between hosts and users
Host subdomain1
User deploy1
Host subdomain2
User deploy2
this way ssh subdomain1
will use the required user deploy1
and the host-ip will be foundqualified to it's full name by resolv.conf