IP Routing (use Aliasing??) on two IP networks

IP Routing (use Aliasing??) on two IP networks

Post by tom willi » Sun, 25 Jun 2000 04:00:00



I have a network with a gateway device and 2 workstations plugged into a

HUB.  Each workstation has been assigned an IP on a different network.
Routing to and from the boxes and the internet is peachy. Routing
between the
boxes goes out the shared gateway and back, it seems, so it is not as
fast as it could
be.  How do I change routing or use IP aliasing or something to make
direct (much faster!) connections between Box 1 and Box 2,
preferably without resorting to a second set of NICs and a second HUB.

                                            + Box 1 IP 1.2.3.4
                                            |
GW ======= HUB ==+
IP 2.3.4.5                           |
                                            + Box 2 IP 3.4.5.6

TIA

-tom

 
 
 

IP Routing (use Aliasing??) on two IP networks

Post by Duncan Simps » Tue, 27 Jun 2000 04:00:00



Quote:>I have a network with a gateway device and 2 workstations plugged into a
>HUB.  Each workstation has been assigned an IP on a different network.
>Routing to and from the boxes and the internet is peachy. Routing
>between the
>boxes goes out the shared gateway and back, it seems, so it is not as
>fast as it could
>be.  How do I change routing or use IP aliasing or something to make
>direct (much faster!) connections between Box 1 and Box 2,
>preferably without resorting to a second set of NICs and a second HUB.
>                                            + Box 1 IP 1.2.3.4
>                                            |
>GW ======= HUB ==+
>IP 2.3.4.5                           |
>                                            + Box 2 IP 3.4.5.6

Use host or network routes. In partucalr network routes allow you to
run multiple networks along the same peices of coax (or hub, switch,
screen, etc). Having said that doing this is silly----why not just use
one network instead?

OK, there are some situations, for example a network shared by
machines in private IP space (at least partly for their proetction)
and some things they need to talk to in public IP space.

P.S. If you do not have enough public IP space plese ensure you use
*privte IP space* for the hosts you hide behind the NAT box.

--
Duncan (-:
"software industry, the: unique industry where selling substandard goods is
legal and you can charge extra for fixing the problems."

 
 
 

1. rtnetlink: network unreachable for Routing for multiple uplinks using ip route add

Dear all,
after playing around and having the same problems on all linux
versions I have at hand and not finding a solution in the net I ask
for your help.

Problem: Want to set up a router with multiple uplinks to the
internet.
Checked documentation at several places, but all examples given will
not work!
Always get rtnetlink: network is unreachable.

Have tried this with IPCop 1.4.5, SUSE Prof. 9.1 same effect.

OK now the details:

For ISP 1 (all IP addresses not the real ones!)
eth0:      10.138.233.227
NETMASK:   255.255.255.240
GW:        10.138.233.226

For ISP2
eth1       10.51.238.226
NETMASK:   255.255.255.240
GW:        10.51.238.226

/etc/rt_tables: (added at end)
200 T1
201 T2

Routing table empty but loopback device when I start:
ip route add 10.138.233.224/28 dev eth0 src 10.138.233.227 table T1
ip route add default via 10.138.233.226 table T1
Error Message: rtnetlink: network is unreachable

ip route add 10.51.238.224/28 dev eth1 src 10.51.238.226 table T2
ip route add default via 10.51.238.225 table T2
Error Message: rtnetlink: network is unreachable

If I use the commands without the table T1/T2 I am able to set the
route. But later it doesn't work.
I took the commands from
   Linux Advanced Routing & Traffic Control HOWTO
   Chapter 4.2
And crosschecked with
    Redundant Internet Connections Using Linux from
    http://www.samag.com/documents/s=1824/sam0201h/0201h.htm

Same effect.
Kernel on Suse9.1:  2.6.4-52
Kernel on IPCop:    2.4.29

Kernel configured with:
    CONFIG_IP_ADVANCED_ROUTER=y
    CONFIG_IP_MULTIPLE_TABLES=y
    CONFIG_IP_ROUTE_MULTIPATH=y

ip version:
    Suse:  iproute2-ss020116
    ipcop: iproute2-ss010824

Any clues?

Thanks in advance
Joerg

2. XFree 3.2A with Trident TGUI 9440 in 16bpp

3. Configuring net (IP-tunnel, IP-Alias, Proxy-ARP, NAT, IP-Masq?)

4. INND - shared writeable mapping

5. Problem: FreeBSD 2.1.5R loses routes when using IP aliasing

6. apache auth hierarchy

7. Helping in using FreeBSD routing with alias IP (on "foreign" net segment)

8. netscape problem

9. IP Aliasing - two networks on the same NIC?

10. Using an IP network address alias on outbound traffic

11. between Network aliasing and IP aliasing???

12. Using Linux to route TCP/IP and IPX packets between networks

13. two IP's on one machine using two differnet NIC's