KB 153

How do I set up a Cisco 678 router to forward GRE for PPTP connections?

Article:153
Created:2002-04-05 11:41:37
Categories:
  Windows 95
  Windows 98
  Windows NT 4
  Windows 2000
  DSL
  Windows XP

Question or Symptom

How do I set up a Cisco 678 router to forward GRE for PPTP connections?

Resolution

From enable mode type:

set nat ent add <internal_machine_ip> 0 47 set nat ent add <internal_machine_ip> 1723 tcp

internal_machine_ip represents your server's local IP address. 0 allows all ports and 47 is for GRE protocol. PPTP is the only VPN protocol that is known to us to work through NAT this way.