Can telnet to localhost but cannot telnet to my LAN IP

Question

I am using Ubuntu 14.04 LTS. I config my /etc/network/interfaces like this:

auto lo
iface lo inet loopback

auto eth0
iface eth0 inet static
address 192.168.5.201
gateway 192.168.5.1
netmask 255.255.255.0
dns-nameservers 8.8.8.8 8.8.4.4

This is my ip addr result:

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:d2:39:2e brd ff:ff:ff:ff:ff:ff
    inet 192.168.5.201/24 brd 192.168.5.255 scope global eth0
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fed2:392e/64 scope link 
       valid_lft forever preferred_lft forever

This is my ifconfig result:

eth0      Link encap:Ethernet  HWaddr 00:0c:29:d2:39:2e  
      inet addr:192.168.5.201  Bcast:192.168.5.255  Mask:255.255.255.0
      inet6 addr: fe80::20c:29ff:fed2:392e/64 Scope:Link
      UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
      RX packets:69923 errors:0 dropped:0 overruns:0 frame:0
      TX packets:47195 errors:0 dropped:0 overruns:0 carrier:0
      collisions:0 txqueuelen:1000 
      RX bytes:57438695 (57.4 MB)  TX bytes:6766887 (6.7 MB)

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:243516 errors:0 dropped:0 overruns:0 frame:0
      TX packets:243516 errors:0 dropped:0 overruns:0 carrier:0
      collisions:0 txqueuelen:1 
      RX bytes:48472222 (48.4 MB)  TX bytes:48472222 (48.4 MB)

I can connect to Internet correctly. I can telnet to my localhost

telnet localhost 9000

But somehow, I cannot telnet to myself using the LAN IP:

telnet 192.168.5.201 9000

telnet: Unable to connect to remote host: Connection refused

My IPTABLES has no rule. Why this happen, and (OR) how can I fix it?

score 3 · Accepted Answer · answered Mar 08 '17 at 03:39

It is probably only listening on localhost. Run sudo netstat -tulpn|grep ':9000'. If the line that comes up says something like 127.0.0.1:9000 then that means I'm correct, in which case you need to modify some sort of a bind-address or listen-address parameter.

Can telnet to localhost but cannot telnet to my LAN IP

1 Answers1