Clients cannot ping each other

fyiuser

Hello!

I use OpenVPN server on my ubuntu machine in cloud.
I have tested the connection between different clients, clients cannot ping each other. Server can ping clients, clients can ping server.

Everything is working fine using different OpenVPN server with the same configurations, I can not determine what is the issue. Could you please suggest what can cause this issue?

Traceroute output:
```
traceroute to 10.8.0.4 (10.8.0.4), 64 hops max, 52 byte packets
1 10.8.0.1 (10.8.0.1) 28.023 ms 19.154 ms 19.272 ms
2 * * *
3 * * *
4 * * *
```

server.conf

```
port 443
proto udp6
dev tun
user nobody
group nogroup
persist-key
persist-tun
keepalive 10 120
topology subnet
server 10.8.0.0 255.255.255.0
ifconfig-pool-persist ipp.txt
push "dhcp-option DNS 208.67.222.222"
push "dhcp-option DNS 208.67.220.220"
push "redirect-gateway def1 bypass-dhcp"
server-ipv6 fd42:42:42:42::/112
tun-ipv6
push tun-ipv6
push "route-ipv6 2000::/3"
push "redirect-gateway ipv6"
dh none
ecdh-curve prime256v1
tls-crypt tls-crypt.key
crl-verify crl.pem
ca ca.crt
cert server_fbNk083zGQPFbr.crt
key server_fbNk0c3zGQPFbr.key
auth SHA256
cipher AES-128-GCM
ncp-ciphers AES-128-GCM
tls-server
tls-version-min 1.2
tls-cipher TLS-ECDHE-ECDSA-WITH-AES-128-GCM-SHA256
status /var/log/openvpn/status.log
verb 3
```

TinCanTech

fyiuser wrote I use OpenVPN server on my ubuntu machine in cloud

fyiuser wrote clients cannot ping each other. Server can ping clients, clients can ping server

fyiuser wrote Could you please suggest what can cause this issue?

Server Firewall.

Openvpn provide --client-to-client, which allows client to see each other and by-passes your server firewall (You may prefer to setup your server firewall correctly, instead).