I have an Ubuntu 14.04 server running some services on different ports. I used to be able to connect to it (via SSH, samba, and a couple web servers on different ports) using a VPN.
I'll use ssh
as an example, but this happens with every port.
When I am trying to connect from within my LAN, everything works fine, but when trying to reach it from my VPN nothing happens (the box gets the tcp packets but not the services listening the ports).
I can connect to other boxes on the network, so I know the VPN works fine.
I can also connect to my box within the network, so I also know
ssh
(and all other services) is up and listening.
Netstat:
$ netstat -ntple
Proto Recv-Q Send-Q Local Address Foreign Address State User Inode PID/Program name
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 0 479 -
- I also used
tshark
to verify that the box is getting something, so I know the routers are working fine.
Output:
$ sudo tshark -i rename2 port 22
Capturing on 'rename2'
1 0.000000 172.17.11.165 -> 10.11.50.93 TCP 74 37478 > ssh [SYN] Seq=0 Win=65535 Len=0 MSS=1360 SACK_PERM=1 TSval=51759576 TSecr=0 WS=256
1 2 3.706230 172.17.11.165 -> 10.11.50.93 TCP 74 41261 > ssh [SYN] Seq=0 Win=65535 Len=0 MSS=1360 SACK_PERM=1 TSval=51760681 TSecr=0 WS=256
2 3 4.697915 172.17.11.165 -> 10.11.50.93 TCP 74 [TCP Retransmission] 41261 > ssh [SYN] Seq=0 Win=65535 Len=0 MSS=1360 SACK_PERM=1 TSval=51760982 TSecr=0 WS=256
3 4 6.730708 172.17.11.165 -> 10.11.50.93 TCP 74 [TCP Retransmission] 41261 > ssh [SYN] Seq=0 Win=65535 Len=0 MSS=1360 SACK_PERM=1 TSval=51761584 TSecr=0 WS=256
4 5 10.697776 172.17.11.165 -> 10.11.50.93 TCP 74 [TCP Retransmission] 41261 > ssh [SYN] Seq=0 Win=65535 Len=0 MSS=1360 SACK_PERM=1 TSval=51762788 TSecr=0 WS=256
I also added/removed rules from the firewall and disabled/restarted
ufw
with no successAlso checked my
iptables
and nothing looks out of place.
Iptables:
$ sudo iptables -L
Chain INPUT (policy ACCEPT)
target prot opt source destination
ACCEPT tcp -- anywhere anywhere tcp dpt:domain
ACCEPT udp -- anywhere anywhere udp dpt:domain
ACCEPT tcp -- anywhere anywhere tcp dpt:bootps
ACCEPT udp -- anywhere anywhere udp dpt:bootps
ACCEPT tcp -- anywhere anywhere tcp dpt:domain
ACCEPT udp -- anywhere anywhere udp dpt:domain
ACCEPT tcp -- anywhere anywhere tcp dpt:bootps
ACCEPT udp -- anywhere anywhere udp dpt:bootps
ACCEPT udp -- anywhere anywhere multiport dports mdns
ACCEPT tcp -- anywhere anywhere multiport dports 4000
ACCEPT tcp -- anywhere anywhere tcp dpt:ssh
ACCEPT tcp -- anywhere anywhere tcp dpt:ssh
Chain FORWARD (policy ACCEPT)
target prot opt source destination
DOCKER-ISOLATION all -- anywhere anywhere
DOCKER all -- anywhere anywhere
ACCEPT all -- anywhere anywhere ctstate RELATED,ESTABLISHED
ACCEPT all -- anywhere anywhere
ACCEPT all -- anywhere anywhere
ACCEPT all -- anywhere anywhere
ACCEPT all -- anywhere anywhere
ACCEPT all -- anywhere anywhere
ACCEPT all -- anywhere anywhere
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
Chain DOCKER (1 references)
target prot opt source destination
Chain DOCKER-ISOLATION (1 references)
target prot opt source destination
RETURN all -- anywhere anywhere
I'm running out of ideas about what might be broken here. The problem appeared few days ago when installing Docker via ssh
with $ curl -fsSL https://get.docker.com/ | sh
, the ssh
connection closed half way trough the installation and couldn't connect anymore. My guess is that the system might have been updated in some way and when docker installed it's network components something got broken. Still can't find what.
netstat -nr -4
output:
$ netstat -nr -4
Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt Iface
0.0.0.0 10.11.50.1 0.0.0.0 UG 0 0 0 rename2
10.0.3.0 0.0.0.0 255.255.255.0 U 0 0 0 lxcbr0
10.11.50.0 0.0.0.0 255.255.255.0 U 0 0 0 rename2
172.17.0.0 0.0.0.0 255.255.0.0 U 0 0 0 docker0
ifconfig
output:
$ ifconfig
docker0 Link encap:Ethernet HWaddr 02:42:06:f0:a2:16
inet addr:172.17.0.1 Bcast:0.0.0.0 Mask:255.255.0.0
UP BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)
eth6 Link encap:Ethernet HWaddr 8c:dc:d4:2c:24:b6
UP BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)
Interrupt:20 Memory:d3300000-d3320000
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:8329 errors:0 dropped:0 overruns:0 frame:0
TX packets:8329 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:1311610 (1.3 MB) TX bytes:1311610 (1.3 MB)
lxcbr0 Link encap:Ethernet HWaddr 02:2f:b6:06:aa:d6
inet addr:10.0.3.1 Bcast:0.0.0.0 Mask:255.255.255.0
inet6 addr: fe80::2f:b6ff:fe06:aad6/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:785 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:0 (0.0 B) TX bytes:222126 (222.1 KB)
lxdbr0 Link encap:Ethernet HWaddr fe:21:66:ba:91:98
inet6 addr: fe80::1/64 Scope:Link
inet6 addr: fe80::3007:bfff:fe70:8407/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:14 errors:0 dropped:0 overruns:0 frame:0
TX packets:31 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:968 (968.0 B) TX bytes:6130 (6.1 KB)
rename2 Link encap:Ethernet HWaddr 8c:dc:d4:2c:24:b7
inet addr:10.11.50.93 Bcast:10.11.50.255 Mask:255.255.255.0
inet6 addr: fe80::8edc:d4ff:fe2c:24b7/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:312920 errors:0 dropped:0 overruns:0 frame:0
TX packets:33140 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:51883472 (51.8 MB) TX bytes:6473301 (6.4 MB)
Memory:d3100000-d3180000
vethD4RBEX Link encap:Ethernet HWaddr fe:21:66:ba:91:98
inet6 addr: fe80::fc21:66ff:feba:9198/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:14 errors:0 dropped:0 overruns:0 frame:0
TX packets:64 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:1164 (1.1 KB) TX bytes:11813 (11.8 KB)
ifconfig
andnetstat -nr -4
to your question ?rename2
).docker0
and it works normally. Feel free to post this as an answer. Thanks.