getent is a Unix command that helps a user get entries in a number of important text files called databases

• https://en.wikipedia.org/wiki/getent
• http://linux.die.net/man/1/getent

The databases it searches in are: ahosts, ahostsv4, ahostsv6, aliases, ethers (Ethernet addresses), group, gshadow, hosts, netgroup, networks, passwd, protocols, rpc, services, and shadow.