cannot see hosts on network

Tom Douglas · 12-28-2007, 06:28 PM

Hi, Folks!

My Fedora 7 box is not seeing anything on the network. Another box using Fedora 8 DOES see my f7 and WinXP boxes.

I troubleshot as follows:
* Both Fedora boxes had smb restarts.
* iptables on both boxes are shut down.
* Getting pings from the f8 from the f7 box.

Can anyone tell me what I need to see all the hosts on my Either LAN?

Thank you!

Tom D.

jay73 · 12-28-2007, 06:45 PM

Have you had a look at your /etc/hosts file?

Tom Douglas · 12-31-2007, 08:56 AM

Quote:

Have you had a look at your /etc/hosts file?

Here's what in my /etc/hosts file. Just a list of hosts that I'd expect to see on the network list.

Code:

127.0.0.1	localhost	
192.168.1.1	tom	
192.168.1.31	road-runner	
192.168.1.51	snow-white

Tom D.

jay73 · 12-31-2007, 11:10 AM

Have you tried inserting the fully qualified domain names for the other computers (e.g. tom.foo.com)?

mohtasham1983 · 12-31-2007, 10:47 PM

Are you trying to share files in samba???

To see information about other computers in the network, I recommend you install a very useful tool called nmap. Once you install nmap you can obtain a lot of useful information about other computers and the network.

For example, if your local IP is 192.168.1.100, if you issue the following command you can see all the computers that have port 80 open.:

PHP Code:



 nmap -p 80 192.168.1.0-255

It's also very useful for troubleshooting. You can also see all open ports of your computer using the following command:

PHP Code:



 nmap localhost

For your specific problem, I guess there is something wrong with the sambe client configuration. I'm not sure about this, but I guess you cannot have both samba client and server running at the same time on linux.

jay73 · 12-31-2007, 11:43 PM

I would doubt that it is a SAMBA issue, or at least not that alone. OP states that he can't see his other Linux boxes either.

Tom Douglas · 01-01-2008, 10:44 AM

Quote:

Originally Posted by jay73

Have you tried inserting the fully qualified domain names for the other computers (e.g. tom.foo.com)?

Jay, are you talking about adding fully qualified domain names to the /etc/hosts file?

Code:

192.168.1.1	tom	tom.toms.net
192.168.1.31	road-runner	road-runner.toms.net
192.168.1.51	snow-white	snow-white.toms.net

I don't have these FQDN's on my other boxes that does see what's on my private LAN.

Tom D.

Tom Douglas · 01-01-2008, 11:28 AM

[QUOTE=mohtasham1983;3007225]Are you trying to share files in samba???

To see information about other computers in the network, I recommend you install a very useful tool called nmap. Once you install nmap you can obtain a lot of useful information about other computers and the network./QUOTE]

Yes, I'm trying to run Samba, and others. I don't see host on the "Linux network" nor Windows (Samba) hosts, as I can from other boxes.

I tried nmap as you suggested that got the following result:

Code:

(root@snow-white tom)# nmap -p 137 192.168.1.0-255

Starting Nmap 4.20 ( http://insecure.org ) at 2008-01-01 10:05 MST
Interesting ports on snow-white (192.168.1.51):
PORT    STATE  SERVICE
137/tcp closed netbios-ns

Nmap finished: 256 IP addresses (1 host up) scanned in 6.548 seconds
(root@snow-white tom)#

I also ran this on ports 138 and 139, seeing that's what Samba uses, showing identical readings. Does this tell me that that the 137:139 ports are closed? This is with iptables shut down. I checked my Samba config GUI and things seem to be in order.

Another thing....I'm getting really suspicious with my Ethernet port. I haven't been able to ping out of this box in question, so I set the eth0 port to a static IP address just to take the DHCP out of the picture. I can now ping out, and ping in from other boxes. Still not able to see any hosts from this box, not even itself.

What's interesting is a folder-in-net icon is now showing up, labeled "SFTP File Transfer on snow-white". Another Linux box sees this also. I didn't set this up, nor have seen anywhere before. Is this related to Samba? Or...what's up with this?

Tom D.

mohtasham1983 · 01-01-2008, 03:13 PM

I think you are having network issues. That nmap command should return the number of connected hosts to the specified network even though they have port 137 closed.

Did you try running nmap localhost and nmap <your IP address>?

Can you see any difference between the results of these two commands?

Tom Douglas · 01-01-2008, 05:53 PM

Quote:

Originally Posted by mohtasham1983

I think you are having network issues. That nmap command should return the number of connected hosts to the specified network even though they have port 137 closed.

Did you try running nmap localhost and nmap <your IP address>?

Can you see any difference between the results of these two commands?

There's no difference between the host name, static IP address, or local host. Same results.

I updated net-tools RPM; no help. Are there other RPM's that should be looked at relating to the network service?

I can ping this and get in with VNC and FTP; nothing else, not even Samba. Why would VNC and FTP work and nothing else? Weird.... I'm downloading Samba updates although I'm still suspicious with the network server.

Other threads seem to indicate issues on Fedora 7 (which I'm using).....Ethernet port works initially, then just breaks. My only work-around is changing my port from DHCP to static IP address.

Tom D.

Tom Douglas · 01-01-2008, 06:29 PM

I just rebooted my Fedora 7 box and now it's showing up on the network. Plus this box sees other hosts on the network. So the net-tools RPM have have helped -- that's the only upgrade I made.

The only thing I need to get rid of is this "SFTP File Transfer" node on the network. Any ideas how to accomplish this? It's still there after shutting down ssh.

Gettin' close!

Tom D.