Linux - NetworkingThis forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.
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I build a linux box setup as my gateway for my 3 other computers. This box has 4 NICs
eth0: an NE2000 ISA 10Mbps. Connect to my cable modem
The rest of them are 10/100Mbps
eth1: 3Com Corporation 3c905B 100BaseTX [Cyclone] (rev 30)
eth2: Realtek 8139 chip type 'RTL-8139C'
eth3: Realtek 8139 chip type 'RTL-8139B'
Quote:
dmesg | grep eth
NE*000 ethercard probe at 0x300: 00 40 05 f7 04 f3
eth0: NE2000 found at 0x300, using IRQ 3.
eth2: RealTek RTL8139 at 0x6300, 00:50:fc:56:19:e8, IRQ 11
eth2: Identified 8139 chip type 'RTL-8139C'
eth3: RealTek RTL8139 at 0x6400, 00:60:67:77:8a:b9, IRQ 9
eth3: Identified 8139 chip type 'RTL-8139B'
eth1: Media override to transceiver 4 (100baseTX).
eth2: link up, 100Mbps, full-duplex, lpa 0x45E1
eth3: link up, 100Mbps, full-duplex, lpa 0x45E1
More details about my network
eth0 is my cable modem connection
eth1 is 192.168.1.0 network connected to Windows PC with Intel Pro 10/100 NIC
eth2 is 192.168.2.0 network connected to Linux box with Intel Pro 10/100 NIC
eth3 is 192.168.3.0 network connected to Linux box as my mail and ftp server with VIA Rhine NIC
The problem is the transfer rate between LAN is very very slow. I tried to download from my ftp server from the other boxes but only get 2000-2500 kbps. I think it should be much much higher than that (around 10000 kbps for 100MBps network).
I find it interresting that your internal IP's are in the form 192.168.X.0. If the netmask you are using is 255.255.255.0, then each computer would be viewed as being on a different network, and this could cause many problems, even 'host un-reachable' With a netmask of 255.255.0.0, then these would all be on the same network. Tyupically, though 255.255.255.0 is assumed, unless you specify a different netmask.
The better way to setup internal IP's on the same network would be with IP addresses in the form of 192.168.0.X or 192.168.1.X, where X is different for each machine.
The internal IP address of your cable modem is important as well. Each network interface has at least one IP address. The cable modem would have 2 - one that's publicly routable, assigned by your ISP, and one that's internal. Check your cable modem's configuration for this, and then setup your internal IP addresses so they are on the same internal network using IP addresses like: 192.168.C.X where C is the same number that the cable modem has in that place, and X changes with each machine.
Other possible issues may be a bad NIC card. sometimes NICs fail, and talk on the network when they shouldn't. This should cause collisions, as more than one device is talking at the same time. You can test for this by un-pluging each computer, one at a time, test the network, then plug it back in, and move to the next.
From your post, It appears that eth2 and eth3 have issues, with eth2 having more errors, dropped packets, etc...
If your network basically works, I'd look at eth2 first, netmask settings second, and IP addressing schemes last.
Actually, it looks like the client that's sending to eth2 has a bad NIC card - because of the RX errors. There could be other issues as well - is that NIC cable running near a power line? even a power cord to a lamp, fan, the computer's power cord it's self could be bleeding into the NIC cable. Try re-routing that cable, and see what happens, try replacing that cable.
Actually this problem started when I replaced my linux gateway. The one I mentioned as my mail and ftp server was my linux gateway. With this machine serving the gateway, I didn't have any problem with the slow transfer rate. I used the same NIC card.
Other comment is about my subnet, I will try to change my netmask. I don't think seperating the network will cause this kind of issue.
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