[GRLUG] IPSec & CentOS

[Adam Tauno Williams]

I'm trying to setup an IPSec connection where one end is a CentOS box.
This seems pretty straight forward according to the manual
<http://www.linuxtopia.org/online_books/centos_linux_guides/centos_linux_security_guide/s1-ipsec-net2net.html>.  Currently I'm just using a simple pre-shared key (PSK).  But it doesn't get as far as even failing in some interesting way:

[root at vpn ~]# ifup ipsec0
RTNETLINK answers: Invalid argument

That response is immediate.

The only output seems to be in /var/log/messages:

kernel: NET: Registered protocol family 10
kernel: lo: Disabled Privacy Extensions
kernel: IPv6 over IPv4 tunneling driver
kernel: NET: Registered protocol family 15
racoon: ERROR: racoon: MLS support is not enabled. 
racoon: INFO: @(#)ipsec-tools 0.6.5
(http://ipsec-tools.sourceforge.net) 
racoon: INFO: @(#)This product linked OpenSSL 0.9.8b 04 May 2006
(http://www.openssl.org/) 
racoon: INFO: 127.0.0.1[500] used as isakmp port (fd=8) 
racoon: INFO: 127.0.0.1[500] used for NAT-T 
racoon: INFO: X.X.X.X[500] used as isakmp port (fd=9) 
racoon: INFO: X.X.X.X[500] used for NAT-T 
racoon: INFO: 192.168.1.72[500] used as isakmp port (fd=10) 
racoon: INFO: 192.168.1.72[500] used for NAT-T 
racoon: INFO: ::1[500] used as isakmp port (fd=11) 
racoon: INFO: fe80::250:56ff:fea8:5816%eth0[500] used as isakmp port
(fd=12) 
racoon: INFO: fdb5:60da:9b8a:1:250:56ff:fea8:7d21[500] used as isakmp
port (fd=13) 
racoon: INFO: fe80::250:56ff:fea8:7d21%eth1[500] used as isakmp port
(fd=14) 

- where X.X.X.X is the public interface of the host.

Any ideas?  It is such a helpful error message.