dhcp3-relay software package provides virtual package provided by isc-dhcp-relay, you can install in your Debian 7 (Wheezy) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install dhcp3-relay
dhcp3-relay is installed in your system.
Make ensure the dhcp3-relay package were installed using the commands given below,
$ sudo dpkg-query -l | grep dhcp3-relay*
You will get with dhcp3-relay package name, version, architecture and description in a table
| Distro | Debian 7 wheezy |
| Section | Virtual packages |
| Package | dhcp3-relay |
| Version | |
| Description | virtual package provided by isc-dhcp-relay |
| Sub Section | virtual |