Private LAN setup with redhat 9 help

ezeke1 · 11-16-2004, 12:29 PM

Here you go guys, this is the output for 'ifconfig -a' , 'iptables -L -v -n' and my route dump.
I've disabled iptables and there are no policies configured so I'm not sure if this is an issue. Unless I need a policy to allow for packets to come in and out?

[root@scorpions]# ifconfig -a
eth0 Link encap:Ethernet HWaddr 00:03:47:29:5A:C3
inet addr:10.0.1.1 Bcast:10.0.1.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:28046157 errors:0 dropped:0 overruns:0 frame:0
TX packets:29003379 errors:28 dropped:0 overruns:0 carrier:28
collisions:1376057 txqueuelen:100
RX bytes:329315961 (314.0 Mb) TX bytes:4109504358 (3919.1 Mb)
Interrupt:11 Base address:0xd880 Memory:feaef000-feaef038

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:7938870 errors:0 dropped:0 overruns:0 frame:0
TX packets:7938870 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:571597125 (545.1 Mb) TX bytes:571597125 (545.1 Mb)

[root@scorpions]# iptables -L -v -n
Chain INPUT (policy ACCEPT 34M packets, 9282M bytes)
pkts bytes target prot opt in out source destinatio

Chain FORWARD (policy ACCEPT 0 packets, 0 bytes)
pkts bytes target prot opt in out source destinatio

Chain OUTPUT (policy ACCEPT 37M packets, 17G bytes)
pkts bytes target prot opt in out source destinatio

~ > route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
10.0.1.3 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
0.0.0.0 131.198.115.1 0.0.0.0 UG 0 0 0 eth0

Thanks

gani · 11-17-2004, 04:55 AM

It appeared to me that you have high counts of collisions. Do you have spare NICs and a Hub/Switch? Try to isolate. It could be harware or cable causing it.

Is the "route -n" dump from other box? Its IP is different from what is in your eth0's "ifconfig -a" dump. It looks to me that your route is okey though noticed that in "route -n" eth0 is 10.0.1.3 whereas in your "ifconfig -a" it's 10.0.1.1. If this is in the same box, this could be a problem.

You can try to view this config file: /etc/sysconfig/network-scripts/ifcfe-eth0. For what I can recall (coz I'm no longer using RH) your network settings are stored here. As with Slackware it is in /etc/rc.d/rc.inet1.conf (not quite sure also since I also stopped using Slackware). Sometimes I just don't need to run ifconfig to change my IP, netmask and gateway, I just have to edit this file via vi or joe or whaterver.

Try to change all your netmask to 255.0.0.0.

Since you disabled your firewall and that all your chains' defalult policy is ACCEPT, you should be able to accept connections from everywhere. Though still ask others opinion coz I'm not that really familiar with iptables coz I'm using OpenBSD's PF instead as firewall.

This is what I can give based on my very limited knowledge. I still consider myself a newbie.

gani · 11-17-2004, 05:22 AM

/etc/sysconfig/network-scripts/ifcfg-eth0

scowles · 11-17-2004, 05:41 AM

Quote:

Originally posted by gani
Is the "route -n" dump from other box? Its IP is different from what is in your eth0's "ifconfig -a" dump. It looks to me that your route is okey though noticed that in "route -n" eth0 is 10.0.1.3 whereas in your "ifconfig -a" it's 10.0.1.1. If this is in the same box, this could be a problem.

Good point! Plus there is no network address route defined for eth0. The output of "route -n" should look the same on both systems. Only the output of ifconfig should be different. i.e .The IP address. Also note that the default gateway should fall within the host address range for the network address (192.168.8.0/24 in my example).

Box 1

Code:

[root@excelsior root]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
192.168.8.0     0.0.0.0         255.255.255.0   U     0      0        0 eth0
0.0.0.0         192.168.8.1     0.0.0.0         UG    0      0        0 eth0

[root@excelsior root]# ifconfig eth0
eth0      Link encap:Ethernet  HWaddr 00:60:97:14:71:34  
          inet addr:192.168.8.2  Bcast:192.168.8.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:1484274 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1766864 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:271511419 (258.9 Mb)  TX bytes:541492504 (516.4 Mb)
          Interrupt:10 Base address:0x6800

Box 2

Code:

[root@voyager root]# route -n                                             
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
192.168.8.0     0.0.0.0         255.255.255.0   U     0      0        0 eth0
0.0.0.0         192.168.8.1     0.0.0.0         UG    0      0        0 eth0

[root@excelsior root]# ifconfig eth0
eth0      Link encap:Ethernet  HWaddr 00:60:97:14:B1:C4  
          inet addr:192.168.8.3  Bcast:192.168.8.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:2284571 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1963528 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:486612462 (468.9 Mb)  TX bytes:531342201 (520.1 Mb)
          Interrupt:10 Base address:0x6800

gani · 11-17-2004, 05:50 AM

The default gateway could be his ISP's gateway: 131.198.115.1?

mskahlon · 11-17-2004, 05:59 AM

try using class c ip addresses with network mask 255.255.255.0 cause class a ip address sometimes create ploblems...

mskahlon · 11-17-2004, 06:00 AM

try using class c ip addresses with network mask 255.255.255.0 for a single network..

scowles · 11-17-2004, 07:03 AM

Quote:

Originally posted by gani
The default gateway could be his ISP's gateway: 131.198.115.1?

True! If the output of ifconfig -a showed another interface like ppp0, eth1, etc... Given that ifconfig -a only shows eth0 and lo, there is no way that the default route can work as shown. Which of the "defined" interfaces will issue an arp for the 131.198.115.1 address? None of the defined interfaces/routes (as shown) fall within the host address range/network address.

ezeke1 · 11-17-2004, 08:01 AM

I'd like to thank everyone for their insightful input. The discrepancies found are due to me copying and pasting configs from a totally different machine. The computers I'm having problems with are in a secure lab so there is really no way for me to easily copy and paste the stuff for everyone to see.

After further troubleshooting and some assistance I was able to get the machines to ping one another. To be honest I don't think I know what the problem was but after playing around with the configs I ruled out that routes were fine, the firewall issue was fine and basically all config issues were fine. I even hardcoded the mac addresses of the opposite machine in the arp table thinking somehow the mac addresses weren't recognized. At one point I would ping a computer and the pings would hang. This indicated to me that packets were sent to the hub but weren't getting to the other machine. So after powering down the hub and leaving it offline for a few minutes the problem seemed to clear. My guess is that the hub got confused during all the changes and simply wasn't advertising to its ports. I'm still not sure but that's the best I can come up with.

Thanks again all

gani · 11-18-2004, 05:27 AM

Your high counts of collisions indicate that there is something wrong with your hardware. It could be that your hub just needs resetting.