mlvpn server does not open ports #143
Description
Hi,
We are seeing a situation where mlvpn does not open any of the UDP ports on the server side.
config:
[general]
statuscommand = "/etc/mlvpn/mlvpn0_updown.sh"
tuntap = "tun"
mode = "server"
interface_name = "mlvpn0"
timeout = 30
password = "pleasechangeme!"
reorder_buffer_size = 64
loss_tolerence = 50
[filters]
[isp1]
bindport = 5080
[isp2]
bindport = 5081
Netstat output
# netstat -tulpana
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 127.0.0.53:53 0.0.0.0:* LISTEN 13426/systemd-resol
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 897/sshd
tcp 0 1080 172.31.111.23:22 2.2.2.2:54520 ESTABLISHED 25445/sshd: [accept
tcp 0 340 172.31.47.212:22 1.1.1.1:53580 ESTABLISHED 15836/sshd: ubuntu
tcp6 0 0 :::22 :::* LISTEN 897/sshd
udp 0 0 127.0.0.53:53 0.0.0.0:* 13426/systemd-resol
udp 0 0 172.31.47.212:68 0.0.0.0:* 713/systemd-network
Strace shows that the process is stuck after binding the ports and running read()
socket(AF_INET6, SOCK_DGRAM|SOCK_CLOEXEC, IPPROTO_IP) = 4
connect(4, {sa_family=AF_INET6, sin6_port=htons(5081), inet_pton(AF_INET6, "::1", &sin6_addr), sin6_flowinfo=htonl(0), sin6_scope_id=0}, 28) = 0
getsockname(4, {sa_family=AF_INET6, sin6_port=htons(46710), inet_pton(AF_INET6, "::1", &sin6_addr), sin6_flowinfo=htonl(0), sin6_scope_id=0}, [28]) = 0
connect(4, {sa_family=AF_UNSPEC, sa_data="\0\0\0\0\0\0\0\0\0\0\0\0\0\0"}, 16) = 0
connect(4, {sa_family=AF_INET, sin_port=htons(5081), sin_addr=inet_addr("127.0.0.1")}, 16) = 0
getsockname(4, {sa_family=AF_INET6, sin6_port=htons(58360), inet_pton(AF_INET6, "::ffff:127.0.0.1", &sin6_addr), sin6_flowinfo=htonl(0), sin6_scope_id=0}, [28]) = 0
close(4) = 0
write(3, "\2\0\0\0\0\0\0\0", 8) = 8
write(3, "\0\0\0\0", 4) = 4
write(3, "\n\0\0\0", 4) = 4
write(3, "\2\0\0\0", 4) = 4
write(3, "\21\0\0\0", 4) = 4
write(3, "\34\0\0\0", 4) = 4
write(3, "\n\0\23\331\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\1\0\0\0\0", 28) = 28
write(3, "\0\0\0\0", 4) = 4
write(3, "\2\0\0\0", 4) = 4
write(3, "\2\0\0\0", 4) = 4
write(3, "\21\0\0\0", 4) = 4
write(3, "\20\0\0\0", 4) = 4
write(3, "\2\0\23\331\177\0\0\1\0\0\0\0\0\0\0\0", 16) = 16
read(3, <---- stuck here
mlvpn process is alive and shows both link as down, with an exclamation mark !
System information
# lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 18.04.5 LTS
Release: 18.04
Codename: bionic
root@ip-172-31-47-212:/etc/mlvpn# uname -r
5.3.0-1035-aws