Home / ubuntu / Questions / 1044745
In Process
Vinoth Rc
Asked: 2018-06-09 01:55:34 +0800 CST

ping between client to client not working

  • 772

setup Openvpn

Server ip 192.168.70.22 tun0 - 10.8.0.1

Client1 ip 192.168.1.3 tun0 - 10.8.0.6

Client2 ip 192.168.30.44 tun0 - 10.8.0.10

ping tun0 works

ping server from client1 and client2 works vice versa

also IP address ping server ip from client1 and client2 works

But

ping client1 from client2 and server not working

ping client2 from client1 and server not working

vpn ping openvpn 16.04

2 Answers

  1. The result of route -n (**server**)
Kernel IP routing table  
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface  
0.0.0.0         192.168.5.1     0.0.0.0         UG    0      0        0 eth0  
10.8.0.0        0.0.0.0         255.255.255.0   U     0      0        0 tun0  
10.15.0.0       0.0.0.0         255.255.0.0     U     0      0        0 eth0  
192.168.1.0     10.8.0.2        255.255.255.0   UG    0      0        0 tun0  
192.168.2.0     10.8.0.2        255.255.255.0   UG    0      0        0 tun0  
192.168.2.0     0.0.0.0         255.255.254.0   U     0      0        0 eth0  
192.168.5.0     0.0.0.0         255.255.254.0   U     0      0        0 eth0   
192.168.5.66    0.0.0.0         255.255.240.0   U     0      0        0 eth0  

The result of route -n (**client1**)

Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         10.8.0.1        128.0.0.0       UG    0      0        0 tun0
0.0.0.0         192.168.2.1     0.0.0.0         UG    0      0        0 enp0s3
10.8.0.0        0.0.0.0         255.255.255.0   U     0      0        0 tun0
128.0.0.0       10.8.0.1        128.0.0.0       UG    0      0        0 tun0
192.168.1.0     10.8.0.1        255.255.255.0   UG    0      0        0 tun0
192.168.2.0     0.0.0.0         255.255.255.0   U     0      0        0 enp0s3
192.168.5.0     10.8.0.1        255.255.255.0   UG    0      0        0 tun0
192.168.5.66    192.168.2.1     255.255.255.255 UGH   0      0        0 enp0s3

The result of route -n (**client2**)

Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         10.8.0.1        128.0.0.0       UG    0      0        0 tun0
0.0.0.0         192.168.1.1     0.0.0.0         UG    0      0        0 wlp4s0
10.8.0.0        0.0.0.0         255.255.255.0   U     0      0        0 tun0
128.0.0.0       10.8.0.1        128.0.0.0       UG    0      0        0 tun0
192.168.1.0     10.8.0.1        255.255.255.0   UG    0      0        0 tun0
192.168.1.0     0.0.0.0         255.255.255.0   U     0      0        0 wlp4s0
192.168.2.0     10.8.0.1        255.255.255.0   UG    0      0        0 tun0
192.168.5.0     10.8.0.1        255.255.255.0   UG    0      0        0 tun0
192.168.5.66    192.168.1.1     255.255.255.255 UGH   0      0        0 wlp4s0
    • 1

  2. Assuming you have already enabled ipv4 forwarding, you have also:

    1. Inform your clients that VPN server is also a gateway to other VPN clients. You can achieve this by adding this line to your server configuration file:

    push "route 10.8.0.0 255.255.255.0"

    1. Check if your firewall on VPN server allows forwarding packets:

    sudo iptables -A FORWARD -s 10.8.0.0/24 -d 10.8.0.0/24 -j ACCEPT

    If you can't ping clients from VPN server, maybe your clients just do not answer for pings? What os is on your clients?

    • 0