Configuration example for option 77 User-Class (dhcp_poolname_opt=2):

shared-network MyShare {

    # Pool 'user-admin'
    class "pool-admin" {
	match if exists user-class and substring( option user-class, 1, 20 ) = "user-admin";
    }

    # Pool 'user'
    class "pool-generic" {
	match if exists user-class and substring( option user-class, 1, 20 ) = "user";
    }

    # ...

    # pool "user-admin"
    subnet 10.250.130.0 netmask 255.255.255.0 {
       option routers 10.250.130.1;
	pool {
	    allow members of "pool-admin";
	    range 10.250.130.2 10.250.130.250;
	}
    }

    # pool "user"
    subnet 10.250.140.0 netmask 255.255.255.0 {
       option routers 10.250.140.1;
       pool {
	    allow members of "pool-generic";
	    range 10.250.140.2 10.250.140.250;
	}
    }

    # ...
}