Questions Tagged With networking

What Are Facebook Credits?

audrey — Tue, 07 Oct 2014 04:21:41 -0400

Though it is a virtual currency, Credits cost money to buy. As such, it is hard to imagine why anyone would give away free Credits.

Static route in RHEL 6

BigDuphis — Wed, 27 Feb 2013 13:51:04 -0500

I have a box that's on two subnets, both fully routable within the network. I would like to add routing so that all traffic goes to the first adapter, with the exception of a handful of addresses.
I have been able to add the static routes for the individual machines and can get to the secondary adapter, but then when you try to get to the first adapter from one of those machines, then the ping fails. I want to do this for putting certain traffic ie cluster traffic through certain interfaces, but everything needs to be routable within the network.

bond0 --> 10.10.10.10

bond1 --> 10.20.10.10

Ping from another machine on 10.10.10.0 to 10.10.10.10 is good

Ping from another machine on 10.10.10.0 to 10.20.10.10 is bad

Ping from another machine on 10.20.10.0 to 10.10.10.10 is bad

Ping from another machine on 10.20.10.0 to 10.20.10.10 is good

Edit: It looks like I might need to tune something in the arp tunables, but so far arp_ingore/arp_annouce/arp_filter haven't produced any results, but it does sounds like interface base vs host base arp might be the issue.

Policy based routing - configuration with openvpn.

majkelos — Fri, 25 Jan 2013 06:01:02 -0500

I just want to check with you if the config i have made is correct.

I have my goflex with archlinux installed on it. The NAS is connected to the router (router IP is 192.168.100.1)- the NAS IP is 192.168.100.107.

I have the dyndns established so i can connect remotely to my NAS via dlinkddns address. On my router there is the port forwarding set up so all the packets are reaching the NAS and i can use PyLoad and other similar services.

Now i want to establish the openvpn connection from my GoFlex so all the transferr from and to it is secure. Easy enough - i'm just using the

openvpn servername.ovpn

And this is working well - i'm being connected, my address is changed and everybody's happy. But now when i'm trying to connect to my NAS via ddns - it is not giving me the connection. Basically what is happening - i'm sending request via my usuall IP and the NAS is sending the response via my openvpn.

Just for a record these are some basic infos from my machine after openvpn connection:

[root@alarm ~]# ip route
0.0.0.0/1 via 10.200.4.1 dev tun0
default via 192.168.100.1 dev eth0  metric 202
10.200.4.0/22 dev tun0  proto kernel  scope link  src 10.200.5.8
77.92.92.161 via 192.168.100.1 dev eth0
128.0.0.0/1 via 10.200.4.1 dev tun0
192.168.100.0/24 dev eth0  proto kernel  scope link  src 192.168.100.107  metric 202
---------
---------
[root@alarm ~]# ip rule
0:      from all lookup local
32766:  from all lookup main
32767:  from all lookup default
Now i removed the 0.0.0.0/1 via 10.200.4.1 dev tun0 rule:

ip route del 0.0.0.0/1 via 10.200.4.1 dev tun0 And i added 2 new tables called - moja and mvpn in the /etc/iproute2/rt_table file.

Then i set up (i think) source based routing - based on interface - saying that all the traffic comming from eth0 is responding to eth0 and all the traffic comming from tun0 is responding through tun0. :

ip rule add dev tun0 table mvpn
ip route add default dev tun0 table mvpn
ip rule add dev eth0 table moja
ip route add default dev eth0 table moja
ip route flush cache

This seems to work, i mean now when i'm ssh from my NAS and check ipecho.net it gives me different ip (vpn ip) than when i'm checking it via my laptop. So this would be my downloading IP.

My only concern is how to check what is my uploading IP? And assuming it's ok how to make this whole procedure more automatic - preferably together with openvpn connection ? Any tips or ideas?

Ok maybe i'll post the final configs:

[root@alarm ~]# ip route
default via 192.168.100.1 dev eth0  metric 202
10.200.4.0/22 dev tun0  proto kernel  scope link  src 10.200.5.8
77.92.92.161 via 192.168.100.1 dev eth0
128.0.0.0/1 via 10.200.4.1 dev tun0
192.168.100.0/24 dev eth0  proto kernel  scope link  src 192.168.100.107  metric 202
------------
-----------
[root@alarm ~]# ip rule
0:      from all lookup local
32764:  from all iif eth0 lookup moja
32765:  from all iif tun0 lookup mvpn
32766:  from all lookup main
32767:  from all lookup default

Cheers,

Post scriptum: Ok, what i did is i putty to my NAS and then i ssd to my dyn-dns addres - after that i have checked the ssh log file (var/logs/auth.log)

Download speed of router is same as download on laptop with router connected via ethernet

Samprat — Wed, 02 Jan 2013 18:13:08 -0500

Setup -> 1) Wireless Product with Access Point in managed mode say Product Name is Alpha. Alpha has an FTP Server installed in it.

2) Router with Access Point in Master Mode. 3) Net-book with windows 7 installed.

Product IPAddress Net-book 192.168.1.10 Router wi-fi adapter 192.168.1.1 Alpha (wireless Product)waln0 192.168.1.7

Router is connected to net-book via Ethernet cable. The LAN port of Router is connected to Net-book . There is no other connection of Internet or any other wired connection.

My Task is to download the files from alpha to Router and measure download speed of router.

Alpha product is successfully connected to Router and I can ping router from Alpha. At this point I tried to ssh into router from netbook with port 22 but it refused to make connection. How will I make ssh connection? 2) I can ping from my net-book to Alpha. I failed to understand how this work even though I have not connected net-book to router nor to alpha. 3) My main issue is to measure the download speed of router . At this point I can telnet into router but I don’t know username so I failed to login but when I tried to do ftp from net-book to Alpha it works . My question is downloading the files on net-book is same as downloading on router . I am more interested in download speed of router does not care about file downloaded or its contents. Could someone please throw light on it? Thanks ....

To measure throughput of DUT from linux server

Samprat — Fri, 07 Dec 2012 04:36:34 -0500

Description of project->I have a test-tool to which DUT connects. The test-tool has an access-point in it and once DUT get connected to it via mac address we check RSSI and some other features of WiFi of DUT. Now I am wondering is there is any way I can measure throughput of Device under test via mac address of DUT from server side.

Test tool has LINUX fedora 11 in it and major coding is done in c/C++ and json command.

Previously, I have tried to install ftp server on test tool and DUT can connect to it and we can measure the throughput or data transfer rate, but this is not feasible solution as it requires lot of intervention from DUT.

What I am interested in is 1) To run some script on server side /test-tool and it gives me throughput of bandwidth of connected device may be via mac address of DUT OR 2) Server script transfer some files/packets to DUT and we can measure the throughput. Coding is not a major challenge at this stage , I just need some tool which requires minimum intervention from DUT.

ifconfig not showing ppp0 device

unixbhaskar — Sat, 15 Sep 2012 01:37:57 -0400

Same thing on openSUSE 12.2 and Slackware..throw some light.

IP Address

Elad Lending — Wed, 27 Apr 2011 02:58:42 -0400

What is the command (Linux Mint Julia) to discover the IP Address of a computer connected to a wireless router?

backtrack4 ipw2100 module not being loaded for intel pro wireless b lan

rfelsburg — Tue, 19 Apr 2011 02:10:35 -0400

I can't get my wireless card to be used/assigned under backtrack4. I know it works I've used it on other backtrack installs.

Everything seems to point to backtrack recognizing/seeing it, but it's not recognizing the eth1/wlan0/ath0 interface when I try to set it up.

ThoughtS?


root@bt:/usr/local/src/compat-wireless-2.6.38-rc4-1# lshw -C network
 *-network:0
      description: Ethernet interface
      product: 82540EP Gigabit Ethernet Controller (Mobile)
      vendor: Intel Corporation
      physical id: 1
      bus info: pci@0000:02:01.0
      logical name: eth0
      version: 03
      serial: 00:0d:60:b0:c0:ba
      size: 100MB/s
      capacity: 1GB/s
      width: 32 bits
      clock: 66MHz
      capabilities: pm msi bus_master cap_list ethernet physical tp
10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation
      configuration: autonegotiation=on broadcast=yes driver=e1000
driverversion=7.3.21-k6-NAPI duplex=full firmware=N/A ip=10.0.2.4
latency=64 link=yes mingnt=255 module=e1000 multicast=yes port=twisted
pair speed=100MB/s
 *-network:1 UNCLAIMED
      description: Network controller
      product: PRO/Wireless LAN 2100 3B Mini PCI Adapter
      vendor: Intel Corporation
      physical id: 2
      bus info: pci@0000:02:02.0
      version: 04
      width: 32 bits
      clock: 33MHz
      capabilities: pm cap_list
      configuration: latency=64 maxlatency=34 mingnt=2

root@bt:/usr/local/src/compat-wireless-2.6.38-rc4-1# lspci
00:00.0 Host bridge: Intel Corporation 82855PM Processor to I/O
Controller (rev 03)
00:01.0 PCI bridge: Intel Corporation 82855PM Processor to AGP
Controller (rev 03)
00:1d.0 USB Controller: Intel Corporation 82801DB/DBL/DBM
(ICH4/ICH4-L/ICH4-M) USB UHCI Controller #1 (rev 01)
00:1d.1 USB Controller: Intel Corporation 82801DB/DBL/DBM
(ICH4/ICH4-L/ICH4-M) USB UHCI Controller #2 (rev 01)
00:1d.2 USB Controller: Intel Corporation 82801DB/DBL/DBM
(ICH4/ICH4-L/ICH4-M) USB UHCI Controller #3 (rev 01)
00:1d.7 USB Controller: Intel Corporation 82801DB/DBM (ICH4/ICH4-M)
USB2 EHCI Controller (rev 01)
00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev 81)
00:1f.0 ISA bridge: Intel Corporation 82801DBM (ICH4-M) LPC Interface
Bridge (rev 01)
00:1f.1 IDE interface: Intel Corporation 82801DBM (ICH4-M) IDE
Controller (rev 01)
00:1f.3 SMBus: Intel Corporation 82801DB/DBL/DBM (ICH4/ICH4-L/ICH4-M)
SMBus Controller (rev 01)
00:1f.5 Multimedia audio controller: Intel Corporation 82801DB/DBL/DBM
(ICH4/ICH4-L/ICH4-M) AC'97 Audio Controller (rev 01)
00:1f.6 Modem: Intel Corporation 82801DB/DBL/DBM (ICH4/ICH4-L/ICH4-M)
AC'97 Modem Controller (rev 01)
01:00.0 VGA compatible controller: ATI Technologies Inc Radeon RV250
[Mobility FireGL 9000] (rev 02)
02:00.0 CardBus bridge: Texas Instruments PCI4520 PC card Cardbus
Controller (rev 01)
02:00.1 CardBus bridge: Texas Instruments PCI4520 PC card Cardbus
Controller (rev 01)
02:01.0 Ethernet controller: Intel Corporation 82540EP Gigabit
Ethernet Controller (Mobile) (rev 03)
02:02.0 Network controller: Intel Corporation PRO/Wireless LAN 2100 3B
Mini PCI Adapter (rev 04)

root@bt:/usr/local/src/compat-wireless-2.6.38-rc4-1# iwconfig
lo        no wireless extensions.

eth0      no wireless extensions.

irda0     no wireless extensions.

root@bt:/usr/local/src/compat-wireless-2.6.38-rc4-1# ifconfig -a
eth0      Link encap:Ethernet  HWaddr 00:0d:60:b0:c0:ba
         inet addr:10.0.2.4  Bcast:10.0.3.255  Mask:255.255.252.0
         inet6 addr: fe80::20d:60ff:feb0:c0ba/64 Scope:Link
         UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
         RX packets:5388 errors:0 dropped:0 overruns:0 frame:0
         TX packets:4639 errors:0 dropped:0 overruns:0 carrier:0
         collisions:0 txqueuelen:1000
         RX bytes:5188403 (5.1 MB)  TX bytes:983799 (983.7 KB)

irda0     Link encap:IrLAP  HWaddr 00:00:00:00
         NOARP  MTU:2048  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:8
         RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

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:58 errors:0 dropped:0 overruns:0 frame:0
         TX packets:58 errors:0 dropped:0 overruns:0 carrier:0
         collisions:0 txqueuelen:0
         RX bytes:2900 (2.9 KB)  TX bytes:2900 (2.9 KB)

UPDATE:

Found the following code in dmesg. It appears that the firmware module isn't being loaded.


root@bt:~# dmesg 2>&1 | grep ipw
libipw: 802.11 data/management/control stack, git-1.1.13
libipw: Copyright (C) 2004-2005 Intel Corporation <jketreno@<a href="http://linux.intel.com">linux.intel.com>
ipw2100: Intel(R) PRO/Wireless 2100 Network Driver, git-1.2.2
ipw2100: Copyright(c) 2003-2006 Intel Corporation
ipw2100 0000:02:02.0: PCI INT A -> Link[LNKC] -> GSI 11 (level, low) -> IRQ 11
ipw2100: Detected Intel PRO/Wireless 2100 Network Connection
ipw2100: eth1: Firmware 'ipw2100-1.3.fw' not available or load failed.
ipw2100: eth1: ipw2100_get_firmware failed: -2
ipw2100: eth1: Failed to power on the adapter.
ipw2100: eth1: Failed to start the firmware.
ipw2100Error calling register_netdev.
ipw2100 0000:02:02.0: PCI INT A disabled
ipw2100: probe of 0000:02:02.0 failed with error -5

Connecting to a wireless network which uses wpa-psk encryption using Backtrack distro

rfelsburg — Tue, 19 Apr 2011 00:11:28 -0400

PROBLEM

I was having a problem setting up wpa_supplicant on backtrack4.

My wireless point uses wpa-psk.

In /etc/network/interfaces:


root@bt:/usr/bin# cat /etc/network/interfaces
auto lo
iface lo inet loopback

#auto eth0
#iface eth0 inet dhcp

auto eth1
iface eth1 inet dhcp
pre-up wpa_supplicant -B -Dwext -i eth1 -c /etc/wpa_supplicant/wpa_supplicant.conf # you might change these bold parameters to suit your wireless card and interface.
post-down killall -q wpa_supplicant

#auto eth2
#iface eth2 inet dhcp
#
#auto ath0
#iface ath0 inet dhcp
#
#auto wlan0
#iface wlan0 inet dhcp

Everything I read said to use wpa_passphrase like below, and delete the commented lines:


root@bt:/usr/bin# wpa_passphrase My_ssid My_ssid_key
network={
        ssid="My_ssid"
        psk=e8a2c6fb04c3537ec1ea7c027b78f96fba46bc5497503dfe0aa2510844e82ce9
}

however this failed miserably with my setup.

Ideas?

Network issue - Redhat 5.4

Ygdrazil — Thu, 17 Mar 2011 10:55:24 -0400

Have a problem where i can not reach a redhat server from different VLAN but if i RDP to a server in same network i can ssh in and after a ping out it is accessible from other networks. This falls out after a while and I have to RDP to win server, ssh in again and ping out to get access from outside again.

Any ideas?

Red Hat Enterprise Linux Server release 5.4 (Tikanga)

load balancing problem

Aditya Pant — Tue, 09 Nov 2010 15:38:53 -0500

HI to all,

In my college's internet laboratory, I want to establish load-balancing:

My network has 2 different ISP net-connections.
I want the both net-connections to be available to all clients.
My Linux-server has 3 LAN cards: eth0 : connected to ISP1 eth1 : connected to ISP2 eth2 : I want to to circulate internet received in eth0 & eth1 to my intranet. HOW CAN I DO?
I do not know how to combine 2 ISP connections into one.

Can you plz. tell me, how to achieve this? Kindly requested to tell me steps or some hyperlink.

regards & thanks in advance

Accessing Win 7 Drives From Linux

BigJohnL — Tue, 02 Nov 2010 19:49:38 -0400

I have a network of mostly Win XP machines, and one Win 7 Ultimate. I'm gradually converting all of them to dual-boot Ubuntu. Simple file-sharing in XP is turned off. All of the Windows machines are networked and mapped to each other.

I can see the XP machines from Ubuntu using Places->Network, and can access them. I can see the Win 7 machine, but cannot access it.

Also, I haven't found the Ubuntu equivalent of Windows' Map Network Drive.

Thanks in advance for the help!

How does one direct traffic to different network interfaces?

Joehillen — Mon, 30 Aug 2010 05:19:34 -0400

Let's say I have two network interfaces, eth0 and eth1, and I want to route traffic from different applications to either one or the other on demand.

How would one do this?

virt-install with VNC, how can i connect to the vnc port from a remote computer?

Zyprexa — Sun, 22 Aug 2010 18:09:11 -0400

I'm trying to install XP Pro on a VM, but how do can i connect to the VNC port from a remote computer?

i create the VM with :

sudo virt-install --name XPComputer --arch x86_64 --vcpus 1 --ram 512 --file /virtpcs/vdisks/harddrive.img --cdrom  /virtpcs/isos/xp_pro_x32.iso --os-type windows --os-variant winxp --keymap no --connect qemu:///system --vnc --vncport 5901 --network bridge:virbr0 --noautoconsole

with netstat -l i can see it's listening on localhost:5901 , but i can't connect to it from the remote computer.

gnome network manager versus /etc/network/interfaces

Matyas — Wed, 21 Jul 2010 14:19:24 -0400

I need some troubleshooting help with a wireless network problem.

I can connect wirelessly using /etc/network/interfaces. ifup wlan0 gets an address via dhcp and all works well. However, I have to click and disable the network manager trying to connect in order for this to work.

If I let gnome network manager connect, it does not succeed. I am getting in daemon.log: NetworkManager: Device 'wlan0' IP6 addrconf timed out or failed.

Interestingly, gnome network manager succeeds in connecting to public networks in coffee shops. This makes me think something is not properly set up at my home router.

Any suggestions? Thanks!

Intel 4965 WiFi refuses to connect to open, unauth AP

Bolster — Mon, 05 Jul 2010 17:10:56 -0400

I have an intel card that refuses to connect to a completely open AP; Win7 has no problem on the same machine, and the machine has no problem connecting to other, secured, AP's. The Access point itself is a Netgear, and the specific wifi care is a intel 4965.

Syslog pickes up a lot of disconnect reason=6 events (see attached) which implies that the AP gave up waiting for authentication, but there is no authentication!

I've been looking for answers on this for a while

usb video storage

Naana — Mon, 21 Jun 2010 13:19:40 -0400

Am working on sending real time video data from an embedded Linux device on to a usb device. Am using the c language. Currently, I have a code that can detect the usb, my challenge is how to send the video data from the camera to the usb device.

Any suggestions?

Thanks in advance.

avahi .local hostname with -2

mildred — Wed, 09 Jun 2010 13:39:24 -0400

I use avahi a lot, and hostnames in .local a lot.

Sometimes, I find that the public hostname is not the local hostname of my computer. Say that my hostname is meryl, I find that on the local network it is called meryl-2.local instead of meryl.local

That might be caused by the fact that sometimes the laptop is connected to the network both by wifi and ethernet (wifi is too slow for data transfer). So because there was a conflict in names, it renamed the local host.

Now, when I have only one connexion active, I'd like my hostname to be meryl.local

Do you know how to do that?

Thanks.

random wireless disconnections (lucid lynx)

dr. Hannibal Lecter — Wed, 09 Jun 2010 11:18:47 -0400

I'm using Ubuntu 10.04 and I'm having problems with my wireless connection. It simply stops working randomly.

I thought the cause might be a number of connections or something like that, but it's not. Sometimes it stops working while you're off doing something unrelated to the network.

Also, once it stops working, I'm unable to connect anymore until I reboot the machine. Some say it might be a problem with NetworkManager, but I can't use the recommended wicd because it won't even connect (it seems like hidden SSID + wep bothers wicd).

I'd also like to note that I have a windows PC connected to the same router and it never drops a connection like that, so there's obviously nothing wrong with the router.

Any hints would be helpful. I'd like to drop NM altogether if possible, but I'm not aware of any good alternative.

Edit:

lecterror@feck:~$ lspci -nnk | grep -i net -A2
07:00.0 Network controller [0280]: Intel Corporation Wireless WiFi Link 5100 [8086:4232]
    Kernel driver in use: iwlagn
    Kernel modules: iwlagn
09:00.0 Ethernet controller [0200]: Broadcom Corporation NetXtreme BCM5764M Gigabit Ethernet PCIe [14e4:1684] (rev 10)
    Kernel driver in use: tg3
    Kernel modules: tg3

lecterror@feck:~$ rfkill list
0: acer-wireless: Wireless LAN
    Soft blocked: no
    Hard blocked: no
1: acer-bluetooth: Bluetooth
    Soft blocked: yes
    Hard blocked: no
3: phy0: Wireless LAN
    Soft blocked: no
    Hard blocked: no

sudo iwlist scan got me a large list of available networks, I'm assuming you don't need it if that's the expected output :)

Edit 2:

No dice! :( My "solution" in the answers below didn't work, in fact it made everything worse, disconnections every few seconds. dmesg said this:

[ 1170.188961] wlan0: deauthenticating from XXXXXX by local choice (reason=3)

I have no idea what it means, but it sure as hell wasn't by MY local choice!

For now I've reverted to NetworkManager and the funny thing is that is seems more stable than before(?). Possibly due to WEP->WPA switch, but I can't be sure..

Any ideas?

I can ping google/yahoo and others, but not msn?

Mark D. — Mon, 10 May 2010 13:45:06 -0400

Greetings -

I'm running slackware 64/13.0 and recently setup my wireless card and it's working fine, until I tried to ping or connecg with msn. msn is my isp. I've got DSL and my /etc/resolve.conf file's got the following in it:

nameserver 205.171.2.65 nameserver 205.171.3.65

Here's the traceroute. Anybody know why I'm having problems with msn? It's my isp?

traceroute www.msn.com traceroute to www.msn.com (65.55.17.27), 30 hops max, 38 byte packets 1 dslmodem.domain.actdsltmp (192.168.0.1) 2.099 ms 2.109 ms 1.676 ms 2 blng-dsl-gw04-196.blng.qwest.net (67.42.227.196) 33.818 ms 33.056 ms 33.920 ms 3 blng-agw1.inet.qwest.net (67.42.227.93) 34.066 ms 34.888 ms 33.902 ms 4 bil-core-01.inet.qwest.net (205.171.154.73) 34.163 ms 33.426 ms 34.503 ms 5 tuk-core-01.inet.qwest.net (205.171.5.142) 52.765 ms 51.959 ms 51.698 ms 6 sea-edge-12.inet.qwest.net (67.14.4.210) 52.391 ms 53.463 ms 52.201 ms 7 63-234-17-26.dia.static.qwest.net (63.234.17.26) 53.086 ms 52.442 ms 52.512 ms 8 ge-7-3-0-58.wst-64cb-1a.ntwk.msn.net (207.46.46.41) 52.493 ms 53.033 ms 52.700 ms 9 ge-3-3-0-0.co2-64c-1a.ntwk.msn.net (207.46.43.194) 58.055 ms 57.948 ms 57.868 ms 10 ge-7-0-0-0.co2-64c-1b.ntwk.msn.net (207.46.43.197) 57.966 ms 57.474 ms 57.208 ms 11 ge-6-0-0-0.co1-64c-1a.ntwk.msn.net (207.46.46.92) 57.062 ms 57.509 ms 56.645 ms 12 10.22.8.177 (10.22.8.177) 57.235 ms 57.230 ms 57.064 ms 13 10.22.8.2 (10.22.8.2) 56.980 ms 57.233 ms 56.398 ms

To connect to internet

Henry — Tue, 04 May 2010 17:01:48 -0400

Hi I'm new to Ubuntu my OS is ubuntu 8.04 LTS I have wired Combo ADSL2+ MOdem/Router (PROLINK5201) I stared with, sudo pppoeconf Then it say sudo unable to resolve host hery -desktop Please help me to connect to internet, I have XP OS too but it is ok Thanks I'M He

network connectivity

moses — Tue, 04 May 2010 10:55:05 -0400

i have both public and private cannot connect to public internet whereas intranet is functional i am using slackware

Connect via SSH/Samba from 1 box to a hidden box (NAT/PAT?) setup?

Ian Vaughan — Wed, 28 Apr 2010 17:02:58 -0400

I need to access a Linux box via SSH & Samba that is hidden/connected behind another one.

Setup :-

  
 A        switch    B         C
|----|    |---|    |----|    |----|
|eth0|----|   |----|eth0|    |    |
|----|    |---|    |eth1|----|eth1|
                   |----|    |----|

Eg, SSH/Samba from A to C

How does one go about this?
I was thinking that it cannot be done via IP alone? Or can it?

Could B say "hi on eth0, if your looking for 192.168.0.2, its here on eth1"?
Is this NAT? This is a large private network, so what about if another PC has that IP?!

More likely it would be PAT?
A would say "hi 192.168.109.15:1234"
B would say "hi on eth0, traffic for port 1234 goes on here eth1"
How could that be done?

And would the SSH/Samba demons see the correct packet header info and work??

IP info :-

A - eth0 - 192.168.109.2
B - eth0 - 192.168.109.15
  - eth1 - 192.168.0.1
C - eth1 - 192.168.0.2

A, B & C are RHEL (RedHat) But Windows computers can be connected to the switch. I configured the 192.168.0.* IPs, they are changeable.

Any help?