Network problems ssh not working.

[marker]

Hi

I am facing the below problem while trying to do ssh from either of the servers.

[stan$ zx100 etc]$ ssh fx100
ssh: connect to host fx100 port 22: Network is unreachable

[stan$fx100 ~]$ ssh zx100
ssh: connect to host zx100 port 22: Network is unreachable


I have added the " ip address to hostname" entries in /etc/hosts on both servers. They are the same on both servers.

And the eth0 interfaces on both servers have been edited with ip addresses and subnet mask. Both servers eth0 have same subnet mask.

But ping from either machine does not work.

Can somebody help me in resolving this problem ? what changes I need to make so that I can connect to either machines.

------------------------------------------

[stan$fx100 ~]$ ssh -v zx100

OpenSSH_4.3p2, OpenSSL 0.9.8e-fips-rhel5 01 Jul 2008
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options for *
debug1: Connecting to zx100 [10.1.36.20] port 22.
debug1: connect to address 10.1.36.20 port 22: Network is unreachable
ssh: connect to host zx100 port 22: Network is unreachable

----------------------

[stan$fx100 ~]$ /sbin/ifconfig
eth0 Link encap:Ethernet HWaddr 00:0C:29:E5:EE:E9
inet addr:10.1.130.1 Bcast:10.1.130.255 Mask:255.255.255.0
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:1000
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
Interrupt:19 Base address:0x2024

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:1400 errors:0 dropped:0 overruns:0 frame:0
TX packets:1400 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:3487475 (3.3 MiB) TX bytes:3487475 (3.3 MiB)


------------------------


[stan$zx100 etc]$ ssh -v fx100
OpenSSH_4.3p2, OpenSSL 0.9.8e-fips-rhel5 01 Jul 2008
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options for *
debug1: Connecting to fx100 [10.1.130.1] port 22.
debug1: connect to address 10.1.130.1 port 22: Network is unreachable
ssh: connect to host fx100 port 22: Network is unreachable

---------------------------------------------------

[stan$zx100 etc]$ /sbin/ifconfig
eth0 Link encap:Ethernet HWaddr 00:0C:29:9C:8D:F3
inet addr:10.1.36.20 Bcast:10.1.36.255 Mask:255.255.255.0
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:1000
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
Interrupt:19 Base address:0x2024

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:1902 errors:0 dropped:0 overruns:0 frame:0
TX packets:1902 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:3537394 (3.3 MiB) TX bytes:3537394 (3.3 MiB)

[awc]

Your machines are in different subnets.

inet addr:10.1.130.1 Bcast:10.1.130.255 Mask:255.255.255.0
inet addr:10.1.36.20 Bcast:10.1.36.255 Mask:255.255.255.0

Try putting both boxes in the same subnet, e.g. make the IP's 10.1.130.1 & 10.1.130.2 Update /etc/hosts too if you want to continue trying to use hostnames.

Not really sure what you mean here

I have added the " ip address to hostname" entries in /etc/hosts on both servers. They are the same on both servers.

If problems continue:

1. Test the ssh server by connecting to the local machine

   ssh localhost

2. Use ip addresses instead of hostnames
3. Check your firewall settings
4. Temporarily turn off Selinux

[marker]

I changed the ip addresses as advised by you. and also made entries on /etc/hosts. But the same problem.

firewall and also the selinux setting have been disabled.


[stan fx100 ~]# ssh 10.1.0.20
ssh: connect to host 10.1.0.20 port 22: No route to host


[stan zx100 ~]$ ssh 10.1.0.21
ssh: connect to host 10.1.0.21 port 22: No route to host

/etc/hosts entry on both servers.

[stan zx100 ~]$ cat /etc/hosts

# Do not remove the following line, or various programs
# that require network functionality will fail.
127.0.0.1 localhost.localdomain localhost
::1 localhost6.localdomain6 localhost6


10.1.0.20 zx100 zx100
10.1.0.21 fx100 fx100

ssh localhost works.

[stan zx100 ~]$ ssh localhost
stan localhost's password:
Last login: Mon Aug 6 23:55:58 2012 from localhost.localdomain

[stan zx100 ~]$

[stan zx100 ~]$ /sbin/ifconfig -a
eth0 Link encap:Ethernet HWaddr 00:0C:29:9C:8D:F3
inet addr:10.1.0.20 Bcast:10.1.0.255 Mask:255.255.255.0
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:1000
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
Interrupt:19 Base address:0x2024

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:6550 errors:0 dropped:0 overruns:0 frame:0
TX packets:6550 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:8537442 (8.1 MiB) TX bytes:8537442 (8.1 MiB)


[stan fx100 ~]# ifconfig -a
eth0 Link encap:Ethernet HWaddr 00:0C:29:E5:EE:E9
inet addr:10.1.0.21 Bcast:10.1.0.255 Mask:255.255.255.0
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:1000
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
Interrupt:19 Base address:0x2024

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:3768 errors:0 dropped:0 overruns:0 frame:0
TX packets:3768 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:5847029 (5.5 MiB) TX bytes:5847029 (5.5 MiB)

[awc]

How are these 2 computers connected?