getent - Unix, Linux Command
NAME
getent - get entries from administrative database
SYNOPSIS
getent database [
key ...]
DESCRIPTION
The
getent program gathers entries from the specified
administrative database using the specified search keys.
Where
database is one of aliases, ethers, group, hosts,
netgroup, networks, passwd, protocols, rpc, services or shadow.
EXAMPLES
1 - Find which service is using specific port
$ getent services 22
ssh 22/tcp
$ getent services 21
ftp 21/tcp
$ getent services 25
smtp 25/tcp mail
2 - Get the info for current logged in user
$ getent passwd `whoami`
root:x:0:0:root:/root:/bin/bash
3 - Perform reverse DNS lookup
$ getent hosts myhost.mydomain.com
15.77.3.40 myhost.mydomain.com myhost