[c-nsp] GRE tunnel to FreeBSD

[Tuc at T-B-O-H.NET]

> 
> On Tue, 24 Oct 2006, Tuc at T-B-O-H.NET wrote:
> 
> TaTBOHN> 	Wondering if anyone had experience with a GRE tunnel to a 
> TaTBOHN> FreeBSD server. 
> TaTBOHN> 
> TaTBOHN> I've set it up on 2 devices on the same subnet. Would this be a problem from
> TaTBOHN> the start? I have my FreeBSD at 192.168.3.21 and gre0 looks like :
> TaTBOHN> 
> TaTBOHN> gre0: flags=9051<UP,POINTOPOINT,RUNNING,LINK0,MULTICAST> mtu 1476
> TaTBOHN>         tunnel inet 192.168.3.21 --> 192.168.3.149
> TaTBOHN>         inet6 fe80::212:3fff:fedd:58b2%gre0 prefixlen 64 scopeid 0x7 
> TaTBOHN>         inet 192.168.3.21 --> 192.168.3.149 netmask 0xffffffff 
> 
> You have incorrect configuration - same ip addresses inside and outside
> tunnel.
> 
	The man page was a little confusing. I saw :

EXAMPLES
     Configuration example:

     Host X-- Host A  ----------------tunnel---------- Cisco D------Host E
               \                                          |
                \                                        /
                 +------Host B----------Host C----------+

     On host A (FreeBSD):

           route add default B
           ifconfig greN create
           ifconfig greN A D netmask 0xffffffff linkX up
           ifconfig greN tunnel A D
           route add E D

     On Host D (Cisco):

           Interface TunnelX
            ip unnumbered D   ! e.g. address from Ethernet interface
            tunnel source D   ! e.g. address from Ethernet interface
            tunnel destination A
           ip route C <some interface and mask>
           ip route A mask C
           ip route X mask tunnelX


	So I did :

ifconfig gre0 create
ifconfig gre0 192.168.3.21 192.168.3.149 netmask 0xffffffff link0 up
ifconfig gre0 tunnel 192.168.3.21 192.168.3.149

	Should the last one be the 2 IPs I want to have the tunnel
IPs be, like :

ifconfig gre0 10.0.1.1 10.0.1.2

	???

			Thanks, Tuc