Wanted to connect via L2TP from an iOS 11 device. But same happens with Windows 10.
```
Mar 23 08:26:28 AC1 xl2tpd[2626]: udp_xmit failed to xxx.xxx.xxx.xxx:63817 with err=-1:No such device
Mar 23 08:26:30 AC1 xl2tpd[2626]: message repeated 2 times: [ udp_xmit failed to xxx.xxx.xxx.xxx:63817 with err=-1:No such device]
Mar 23 08:26:31 AC1 xl2tpd[2626]: udp_xmit failed to xxx.xxx.xxx.xxx:63817 with err=-1:No such device
Mar 23 08:26:33 AC1 xl2tpd[2626]: message repeated 2 times: [ udp_xmit failed to xxx.xxx.xxx.xxx:63817 with err=-1:No such device]
Mar 23 08:26:34 AC1 xl2tpd[2626]: Maximum retries exceeded for tunnel 21254. Closing.
Mar 23 08:26:34 AC1 xl2tpd[2626]: udp_xmit failed to xxx.xxx.xxx.xxx:63817 with err=-1:No such device
Mar 23 08:26:35 AC1 xl2tpd[2626]: udp_xmit failed to xxx.xxx.xxx.xxx:63817 with err=-1:No such device
Mar 23 08:26:35 AC1 xl2tpd[2626]: udp_xmit failed to xxx.xxx.xxx.xxx:63817 with err=-1:No such device
```
configuration used is:
```
cpo@AC1# show vpn l2tp
remote-access {
authentication {
mode radius
radius-server xxx.xx.xxx.xx {
key yyy
}
radius-server xxx.xx.xxx.xx {
key yyy
}
}
client-ip-pool {
start xxx.xxx.xxx.1
stop xxx.xxx.xxx.14
}
dns-servers {
server-1 xxx.xx.xxx.xx
server-2 xxx.xx.xxx.xx
}
idle 180
ipsec-settings {
authentication {
mode pre-shared-secret
pre-shared-secret xxx
}
ike-lifetime 60
lifetime 600
}
mtu 1400
outside-address x.x.x.x
outside-nexthop x.x.x.x
}
```
Probably related to some kernel changes introduced by T583. Falling back to VyOS 999.201802241630 using Kernel `4.4.113-amd64-vyos` works as expected.