I had a recent problem pop up and I have no idea how to fix it. I used to use ssh to log into my desktop via my laptop and vice versa. However, in the last few days, I can not log in at all. Both computers get the internet, both computers have the firewall down, however if I try to log in they say "No route to host" and furthermore, if I try to ping each other the ping cannot find the host. Is there some sort of setting in the router that I missed or something? Any thoughts will be much appreciated because I am completely at a loss. Thanks in advance.

Hi,

can you give your network configurations for both network devices? (ifconfig)

Greetings

Shaddy

Sorry it took me so long to get back. My ifconfig is:

Nieburus:/home/markus # ifconfig
eth0 Link encap:Ethernet HWaddr 00:0BB:A3:5D:A6
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:11

eth1 Link encap:Ethernet HWaddr 00:0B:7D:06:8E:B0
inet addr:192.168.1.102 Bcast:192.168.1.255 Mask:255.255.255.0
inet6 addr: fe80::20b:7dff:fe06:8eb0/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:3 errors:0 dropped:0 overruns:0 frame:0
TX packets:29 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:1240 (1.2 Kb) TX bytes:3210 (3.1 Kb)
Interrupt:5 Memory:fafee000-faff0000

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:16436 Metric:1
RX packets:80 errors:0 dropped:0 overruns:0 frame:0
TX packets:80 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:6170 (6.0 Kb) TX bytes:6170 (6.0 Kb)
On the laptop and:
sweetMachine:/home/markus # ifconfig
eth0 Link encap:Ethernet HWaddr 00:18:F3:6B:65:1A
inet addr:192.168.1.103 Bcast:192.168.1.255 Mask:255.255.255.0
inet6 addr: fe80::218:f3ff:fe6b:651a/64 Scope:Link
UP BROADCAST NOTRAILERS RUNNING MULTICAST MTU:1500 Metric:1
RX packets:406230 errors:0 dropped:0 overruns:0 frame:0
TX packets:316217 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:599384613 (571.6 Mb) TX bytes:23545528 (22.4 Mb)
Interrupt:66 Memory:d7000000-0

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:16436 Metric:1
RX packets:116 errors:0 dropped:0 overruns:0 frame:0
TX packets:116 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:8784 (8.5 Kb) TX bytes:8784 ( 8.5 Kb)

On the desktop. I checked and everything seems fine. Again the firewalls are off, and I cannot even ping the other computers, but both get internet fine and can ping the router as well.

If they are on the same subnet your router has nothing to do with the packets between the 2 hosts.


Can you also post the routing tables from the 2 computers?

netstat -rn



Also paste the ssh command, and resulting output.

The ifconfig output looks OK.

Yeah, the netstat one is:

Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt Iface
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo
0.0.0.0 192.168.1.1 0.0.0.0 UG 0 0 0 eth0

and for the laptop it is the same, except eth0 is eth1(because I am using wireless...)

When I try to ssh, I get:
markus@sweetMachine:~> ssh 192.168.1.102
ssh: connect to host 192.168.1.102 port 22: No route to host

and the ping is:
markus@sweetMachine:~> ping 192.168.1.102
PING 192.168.1.102 (192.168.1.102) 56(84) bytes of data.
From 192.168.1.103: icmp_seq=2 Destination Host Unreachable
From 192.168.1.103 icmp_seq=2 Destination Host Unreachable

but if I ping the router:
PING 192.168.1.1 (192.168.1.1) 56(84) bytes of data.
64 bytes from 192.168.1.1: icmp_seq=1 ttl=64 time=0.544 ms
64 bytes from 192.168.1.1: icmp_seq=2 ttl=64 time=0.543 ms

--- 192.168.1.1 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1000ms
rtt min/avg/max/mdev = 0.543/0.543/0.544/0.023 ms

and both get internet fine. I can also ssh into the computer from the same computer and ssh into my school server:
markus@sweetMachine:~> ssh 192.168.1.103
Password:
Last login: Sun Mar 11 18:22:24 2007 from 192.168.1.103
Have a lot of fun...
markus@sweetMachine:~> ssh cs.du.edu -l mn
Password:
Last login: Sun Mar 11 15:54:24 2007 from c-71-229-250-23
You have old mail.