INTRANET FTP ????

This is one hell of an expectational configuration i am trying here.

Config:
1.> FTP Server running on an Internal machine - 192.168.1.100
2.> To reach this every user has to dial-in a VPN connection, and then
FTP on this server -This server will not be reachable Publically.

This is what i want to do:

1.> Once a VPN connection is successful, the person should ftp to:
ftp.mycompany.com .. instead of 192.168.1.100

How and where can I Set this ?
Will I be required to set up an Intranet.? Do i need to setup an Internal DNS ?
There is currently No Intranet setup here.!


2.> Also I want to have ftp.mycompany.com operate in redundant mode.
i.e; Incase 192.168.1.100 is down, ftp.mycomany.com should be
redirected( either Auto or Manually)to say ... 192.168.1.101

Thanks,
-Paddy