VPN IPSec Openswan

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# 1  
Old 07-15-2014
VPN IPSec Openswan

Hi all,

I have installed Openswan and configured IPSec and works perfect, but for some unknown reasons it stop working. I see that the tunnels are up and established. The route to the destination are added. Everything by the book seems to be ok. But somehow when i start to ping the other side ( private ip ) the packet for that tunnel trying to go out from the interface that have public ip. And for the other tunnel they are not going anyway. All this is on a linux machine CentOS, with eth0 - public ip address, eth0:0 and eth0:1 are private for the tunnels. Can someone help me out here because i need this thing to work ( it's a production ) and i have lost a whole week.

Thanks in advanced !
# 2  
Old 07-19-2014
Can you give us output of

iptables -L 
iptables -t nat -L

# 3  
Old 07-20-2014

As i can see now, the packets start to go through the right interface with the right address but no reply still. The tunnels after a long time it getting established. If i make service ipsec restart ... the first think what iv got from the ipsec auto --up tunnel name or ipsec auto --status is this:

000 #7: "tunnelname":500 STATE_MAIN_I1 (sent MI1, expecting MR1); EVENT_RETRANSMIT in 2s; nodpd; idle; import:admin initiate
000 #7: pending Phase 2 for "tunnelname" replacing #0
After some time the tunnels status is:

000 #22: "tunnelname":500 STATE_QUICK_I2 (sent QI2, IPsec SA established); EVENT_SA_REPLACE_IF_USED in 27637s; newest IPSEC; eroute owner; isakmp#7; idle; import:admin initiate
000 #22: "tunnelname" esp.b18cc17@<pub_ip_other_site> esp.c59dvg@<pub_ip_my_site> tun.0@<pub_ip_other_site> tun.0@<pub_ip_my_site> ref=0 refhim=4294901761
000 #7: "tunnelname":500 STATE_MAIN_I4 (ISAKMP SA established); EVENT_SA_REPLACE_IF_USED in 27870s; newest ISAKMP; lastdpd=-1s(seq in:0 out:0); idle; import:admin initiate
Here is the list of the iptables:

iptables -t nat -L
target prot opt source destination

target prot opt source destination
MYNAT all -- anywhere

Chain OUTPUT (policy ACCEPT)
target prot opt source destination

Chain MYNAT (4 references)
target prot opt source destination
MASQUERADE all -- anywhere anywhere

[Itecor_VPN:main.linux64 ipsec.d]# iptables -L
Chain INPUT (policy ACCEPT)
target prot opt source destination

Chain FORWARD (policy ACCEPT)
target prot opt source destination
ACCEPT all -- anywhere anywhere state RELATED,ESTABLISHED

Chain OUTPUT (policy ACCEPT)
target prot opt source destination
And this is the ping and tracepath results:

PING ( 56(84) bytes of data.
--- ping statistics ---
12 packets transmitted, 0 received, 100% packet loss, time 11338ms

tracepath -n
1?: [LOCALHOST] pmtu 1464
1: 0.943ms pmtu 1446
1: no reply
# 4  
Old 07-21-2014
If you need to redirect traffic from VPN tunnel to eth0 than you must use iptables ro rewrite destination address

iptables -A FORWARD -i eth0:1 -o eth0 -j ACCEPT
iptables -A FORWARD -i eth0:0 -o eth0 -j ACCEPT
iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE

after that you need to enable ipv_4 forwarding

sysctl -w net.ipv4.ip_forward=1

To stay permanent you need to edit /etc/sysctl.conf file

On the other side you must enable input traffic

iptables -A INPUT -s <eth0> -j ACCEPT

# 5  
Old 08-12-2014
Hey thanks for reply,

sorry didn't see that i have mails formatting my pc etc ... about the situation now everything is under control i see that there is some route in the Windows machines so now everything is fine and work perfect ...
thanks again for helping and sorry for the delay !
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