0

Fixed with:

/etc/iproute2/rt_tables 1 tble_eth0

/etc/sysconfig/network-scripts/route-eth0 104.000.64.0/18 dev eth0 src 104.000.65.38 table tble_eth0 default via 104.000.64.1 dev eth0 src 104.000.65.38 table tble_eth0

/etc/sysconfig/network-scripts/rule-eth0 from 104.000.65.38 table tble_eth0

For some reason (I hope you know), after defined gre as default router, my public IP stop ping responding...

I can reach the box from the tunnel, but public IP is dead, and I want to keep it up...

[root@do1 ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
190.999.32.1    0.0.0.0         255.255.255.255 UH    0      0        0 do1
190.999.33.253  0.0.0.0         255.255.255.255 UH    0      0        0 ppp0
107.777.40.74   104.000.64.1    255.255.255.255 UGH   0      0        0 eth0
104.000.64.0    0.0.0.0         255.255.192.0   U     0      0        0 eth0
0.0.0.0         190.999.32.1    0.0.0.0         UG    0      0        0 do1
[root@do1 ~]# ifconfig
do1       Link encap:UNSPEC  HWaddr 00-00-00-00-FF-FF-00-00-00-00-00-00-00-00-00-00
          inet addr:190.999.32.2  P-t-P:190.999.32.1  Mask:255.255.255.255
          UP POINTOPOINT RUNNING NOARP  MTU:1476  Metric:1
          RX packets:817 errors:0 dropped:0 overruns:0 frame:0
          TX packets:761 errors:3 dropped:0 overruns:0 carrier:0
          collisions:3 txqueuelen:0
          RX bytes:45073 (44.0 KiB)  TX bytes:49285 (48.1 KiB)

eth0      Link encap:Ethernet  HWaddr 04:01:37:F1:DC:01
          inet addr:104.000.65.38  Bcast:104.000.127.255  Mask:255.255.192.0
          inet6 addr: fe80::601:37ff:fef1:dc01/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:5046 errors:0 dropped:0 overruns:0 frame:0
          TX packets:4385 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:506257 (494.3 KiB)  TX bytes:459398 (448.6 KiB)

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

[root@do1 ~]#

Basically; I cannot ping 104.000.65.38 from Internet, but I can reach it from tunnel...

I have tried several routing rules, but I put this as simple as possible to see if someone may give us some help.

Thank you!

OnTheFly
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  • Sounds like you want to enable 'split tunneling' google it and see if that's what you're looking for. – Optichip Jan 04 '15 at 23:35

1 Answers1

2

With your current configuration your default gateway is the tunnel itself (do1).

So when you ping 104.000.65.38 from the internet the packets arrive to eth0 but they return via the do1 tunnel instead.

You will need to do connection marking with iptables and set up a secondary routing table with default gateway 104.000.64.1 so that packets that arrive to eth0 get routed back via eth0 and not via do1.

Cha0s
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  • Hi, yes, that is what I have been trying with no success... May you please give me some example? Thank you. – OnTheFly Jan 05 '15 at 14:03
  • I haven't done that on Linux before so I don't have a hands-on example to give you. With a quick search I found the following (that seem to be an easier way to do it even without iptables!) https://unix.stackexchange.com/questions/4420/reply-on-same-interface-as-incoming and https://www.linux-tips.org/article/71/routing-packets-back-from-incoming-interface – Cha0s Jan 05 '15 at 14:13
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    Thank you bro. So, I fixed by adding this: /etc/iproute2/rt_tables 1 tble_eth0 /etc/sysconfig/network-scripts/route-eth0 104.000.64.0/18 dev eth0 src 104.000.65.38 table tble_eth0 default via 104.000.64.1 dev eth0 src 104.000.65.38 table tble_eth0 /etc/sysconfig/network-scripts/rule-eth0 from 104.000.65.38 table tble_eth0 – OnTheFly Jan 06 '15 at 15:52