Why is Mikrotik's local network unavailable?

Question

openvpn

There are three interfaces on the server
eth0 - looks to the Internet
tun0 - Openvpn tunnel 10.10.10.0/24
ppp0 - l2tp tunnel 10.10.11.2-10.10.11.16

iptables -n -L -v --line-numbers
Chain INPUT (policy ACCEPT 14 packets, 1777 bytes)
num   pkts bytes target     prot opt in     out     source               destination         

Chain FORWARD (policy ACCEPT 0 packets, 0 bytes)
num   pkts bytes target     prot opt in     out     source               destination         

Chain OUTPUT (policy ACCEPT 14 packets, 1620 bytes)
num   pkts bytes target     prot opt in     out     source               destination

Clients from both tunnels access the Internet through eth0 without a problem. Clients from OpenVPN L2TP tunnels are also pinged from the server.

netstat -rn
Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
0.0.0.0         55.83.62.1      0.0.0.0         UG        0 0          0 eth0
55.83.62.0      0.0.0.0         255.255.255.0   U         0 0          0 eth0
10.10.10.0      0.0.0.0         255.255.255.0   U         0 0          0 tun0
10.10.11.2      0.0.0.0         255.255.255.255 UH        0 0          0 ppp0

But clients from OpenVPN and L2TP networks do not see each other. What could be the problem?

Answer 1

cat /proc/sys/net/ipv4/ip_forward