Perssitant IP routing between two subnets - Config issues

Data that travels over the air and how to protect (or decipher) it

Perssitant IP routing between two subnets - Config issues

Post by borgy95 on Wed Apr 11, 2012 5:27 am
([msg=65608]see Perssitant IP routing between two subnets - Config issues[/msg])

Hi everyone,

Been bashing away at some netowrking in the linux world recently and coming up trumps on a couple matters...

Im setting up a network with one RHEL6.1 box that acts as a gateway/router into a different subnet it will also be my mail server (lets call it alexandria). alexandria is only required to route traffic from a backtrack machine (lets call it - Invader) to specific clients on a different subnet, only about 3 tops. to start with just one (lets call it victim)

alexandria can currently ping the other subnets gateway (lets suppose the address range is 10.14.x.x) and any other machines within the subnet.. it also has internet access via this subnet (i do not want internet connectivity on alexandria's subnet and it must remain in a different subnet to 'simulate' something coming over the internet.

to start with the theory to check my understanding (cos ultimately im a newb and this is way over my head but the job requires it... so im learning it rapid style :D)once traffic passes through alexandria onto the 10.14.x.x subnet and hits the gateway, the gateway can figure out what to do with the infio using dns/ad so i dont need to worry... i assume thats right?
however alexandria's subnet needs to be told go to the 10.14.x.x and talk to the gateway in 10.14.x.x. so from what i understand that is two steps.
Invader goes to alexandria its gateway/router then gets passed on? and ip routing tables can be used for this?

hopefully that is all correct and makes sense?

so to the problems i have had are that the following files /strings dont seem to exist or so the terminal keeps telling me

Code: Select all
sudo /etc/init.d/networking

from what i understand this is a file i need to permanently edit the static route? can i just create my own?
and the i init.d script is to start the service for netowkring?

I have already enabled the ip forwarding services as checked and confirmed by

Code: Select all
sysctl net.ipv4.ip_forward
net.ipv4.ip_forward = 1

thanks in advance
and i do hope this will eventually be of use to others learning this stuff.

- woops meant to put this in netowkring, sorry mods :oops:
New User
New User
Posts: 4
Joined: Thu Mar 15, 2012 5:02 am
Blog: View Blog (0)

Re: Perssitant IP routing between two subnets - Config issues

Post by FunctionCreep on Thu Apr 12, 2012 3:01 pm
([msg=65637]see Re: Perssitant IP routing between two subnets - Config issues[/msg])

On your first question,

I guess that if you have setup the addresses and subnet masks correctly once a packet of traffic reaches the router, it AND's(or is it XOR(?), double check that if you want) the destination IP of the packet with the available subnet masks addresses and forwards it to the appropriate subnet.

On your second question,

If I understand your objective right, then yes, although you would be using forwarding tables.

On the files not being found,

Are you sure that RHEL carries those utilities in the path you are trying to access them? Haven't used Red Hat in a loooong loooong time, but I think there are variations as to the paths.

Edit: I think the scripts for configuring network devices/interfaces are here in red-hat/fedora distros
Code: Select all
"I hope for nothing. I fear nothing. I am free." ~ Nikos Kazantzakis
User avatar
Experienced User
Experienced User
Posts: 92
Joined: Tue May 18, 2010 6:19 pm
Blog: View Blog (0)

Return to Networking

Who is online

Users browsing this forum: No registered users and 0 guests