Routing Linux 192.168.10.x network to Dlink router on 192.168.1.x network

8/5/2006, 1:23AM

Hi,

Thanks for taking the time to shine some light!

I have a Linux Redhat 7.2 box on a 192.168.10.x network and I have
clients that need to connect also connected to the same Dlink router
which is at 192.168.1.1

All my boxes are physically plugged into the D-link router so they are
all on the same physical network.

I heard that if all machines are on the same router, then all one has
to do is add the odd man out network to the routing page, which I did:


Enable : Yes
Destination IP 192.168.10.100
Netmask : 255.255.255.0
Gateway : 192.168.1.1
Interface :LAN
Metric : 1

My router is on 192.168.1.1
Linux box is on 192.168.10.100
clients on 192.168.1.100

I don't want to be sloppy and change the subnet mask to 255.255.0.0

Shouldn't this work? But my Linux box at 192.168.10.100 can't ping my
D-link router at 192.168.1.1

I could probably do a "route add" command on the Linux box to be able
to ping the D-link, but shouldn't the router, since it's on the same
physical network, see the ping from anything on it's network? Yes...it
should drop it from a different subnet...I know....but since I added
the route in the D-link routing table, shouldn't it not only see it but
route it and/or respond to it?

I can ping the D-link 192.168.1.1 from my boxes on the 192.168.1.x
network.

I don't want to have to add "route print" statements on all my boxes. I
thought this is what routers were for...connecting different subnets?

Thanks for your input!

Thanks,

The "Route Guy"

q4n wrote:
> 8/5/2006, 1:23AM
>
> Hi,
>
> Thanks for taking the time to shine some light!
>
> I have a Linux Redhat 7.2 box on a 192.168.10.x network and I have
> clients that need to connect also connected to the same Dlink router
> which is at 192.168.1.1
>
> All my boxes are physically plugged into the D-link router so they are
> all on the same physical network.
>
> I heard that if all machines are on the same router, then all one has
> to do is add the odd man out network to the routing page, which I did:
>
>
> Enable : Yes
> Destination IP 192.168.10.100
> Netmask : 255.255.255.0
> Gateway : 192.168.1.1
> Interface :LAN
> Metric : 1
That would mean that packets for 192.168.10.100 are to be sent to
192.168.1.1 which probably isn't what you want.

If your 192.168.1.x and 192.168.10.x are on the same subnet, and there
aren't any othe 192.168.y.x on different subnets, then setting the
subnet mask to 255.255.0.0 is what you need to to.

But why doesn't your Linux box have a 192.168.1.x address anyway? Why
don't you just let your router assign its IP address like everybody else's?

Robert

>
> My router is on 192.168.1.1
> Linux box is on 192.168.10.100
> clients on 192.168.1.100
>
> I don't want to be sloppy and change the subnet mask to 255.255.0.0
>
> [snip]

Hi Robert,

Thanks for the reply!

The reason I don't let DHCP do it's dirty deeds is that most of my
boxes are servers or other test clients whose addresses I need to stay
static.

So, opening up my subnet mask is one solution, but in situations where
widening the subnetmask is not desired, shouldn't my router be able to
"route" from one subnet to the other?

I want my 192.168.10.100 to be able to send packets through 192.168.1.1
(The D-link router) to get to 192.168.1.104 and other 192.168.1.x
clients.

Can't I get the D-link to route this way without just opening my subnet
mask?

And does this mean I have to open the subnet mask on all clients and
servers? The reason I ask is that, again, I've read that the router
should be able to handle all of this without changing the clients as
long as they are all plugged into the same router, because the router
gets all the packets, but makes decisions about which to route based on
it's own configured routing table.

I thought I modified the routing table sufficiently with my
> > Enable : Yes
> > Destination IP 192.168.10.100
> > Netmask : 255.255.255.0
> > Gateway : 192.168.1.1
> > Interface :LAN
> > Metric : 1

entry...but apparently not.

Any direction on how to get the router to route without widening the
subnet mask is appreciated!

Sincerely,

RG


Robert Harris wrote:
> q4n wrote:
> > 8/5/2006, 1:23AM
> >
> > Hi,
> >
> > Thanks for taking the time to shine some light!
> >
> > I have a Linux Redhat 7.2 box on a 192.168.10.x network and I have
> > clients that need to connect also connected to the same Dlink router
> > which is at 192.168.1.1
> >
> > All my boxes are physically plugged into the D-link router so they are
> > all on the same physical network.
> >
> > I heard that if all machines are on the same router, then all one has
> > to do is add the odd man out network to the routing page, which I did:
> >
> >
> > Enable : Yes
> > Destination IP 192.168.10.100
> > Netmask : 255.255.255.0
> > Gateway : 192.168.1.1
> > Interface :LAN
> > Metric : 1
> That would mean that packets for 192.168.10.100 are to be sent to
> 192.168.1.1 which probably isn't what you want.
>
> If your 192.168.1.x and 192.168.10.x are on the same subnet, and there
> aren't any othe 192.168.y.x on different subnets, then setting the
> subnet mask to 255.255.0.0 is what you need to to.
>
> But why doesn't your Linux box have a 192.168.1.x address anyway? Why
> don't you just let your router assign its IP address like everybody else's?
>
> Robert
>
> >
> > My router is on 192.168.1.1
> > Linux box is on 192.168.10.100
> > clients on 192.168.1.100
> >
> > I don't want to be sloppy and change the subnet mask to 255.255.0.0
> >
> > [snip]

Hi Route Guy, this is Route Guy:

I got it to work, not by sloppily widening the subnet, but by adding
the route the correct way on the D-link router. After I RTFM, whose
directions are below, I changed the route from this:
Enable : Yes
Destination IP 192.168.10.100
Netmask : 255.255.255.0
Gateway : 192.168.1.1
Interface :LAN
Metric : 1

to this:

Enable : Yes
Destination IP 192.168.10.0 (specifies entire 10.x network)
Netmask : 255.255.255.0 (left same)
Gateway : 0.0.0.0 (0's indicate all clients plugged into one/same
router)
Interface :LAN
Metric : 1 (indicates there are no hops other than to d-link router)

192.168.1.x and 192.168.10.100 talk to each other now like it was high
tea time at the All England Ladies Tea Club.

Thanks for your input!

Love,

RG



Adds a new route to the IP routing table or edits an existing route.
Specifies whether the entry will be enabled or disabled.
The IP address or network that the packets will be attempting to access
Note: 192.168.1.0 with a Netmask of 255.255.255.0 means traffic will be
routed to the entire 192.168.1.x network.
Used to specify which portion of the Destination IP signifies the
network
trying to be accessed and which part signifies the host that the
packets will
be routed to
Note: 255.255.255.255 is used to signify only the host that was entered
in
the Destination IP field.
Specifies the next hop to be taken if this route is used. A gateway of
0.0.0.0
implies there is no next hop, and the IP address matched is directly
connected
to the router on the interface specified: LAN or WAN.
Specifies the interface, LAN or WAN, that the IP packet must use to
transit
out of the router when this route is used.
The amount of hops it will take to reach the Destination IP or network.
A
hop is considered to be traffic passing through a router from one
network to
another. If there is only one router between your network and the
Destination
network, then the Metric value would be 1.
q4n wrote:
> 8/5/2006, 1:23AM
>
> Hi,
>
> Thanks for taking the time to shine some light!
>
> I have a Linux Redhat 7.2 box on a 192.168.10.x network and I have
> clients that need to connect also connected to the same Dlink router
> which is at 192.168.1.1
>
> All my boxes are physically plugged into the D-link router so they are
> all on the same physical network.
>
> I heard that if all machines are on the same router, then all one has
> to do is add the odd man out network to the routing page, which I did:
>
>
> Enable : Yes
> Destination IP 192.168.10.100
> Netmask : 255.255.255.0
> Gateway : 192.168.1.1
> Interface :LAN
> Metric : 1
>
> My router is on 192.168.1.1
> Linux box is on 192.168.10.100
> clients on 192.168.1.100
>
> I don't want to be sloppy and change the subnet mask to 255.255.0.0
>
> Shouldn't this work? But my Linux box at 192.168.10.100 can't ping my
> D-link router at 192.168.1.1
>
> I could probably do a "route add" command on the Linux box to be able
> to ping the D-link, but shouldn't the router, since it's on the same
> physical network, see the ping from anything on it's network? Yes...it
> should drop it from a different subnet...I know....but since I added
> the route in the D-link routing table, shouldn't it not only see it but
> route it and/or respond to it?
>
> I can ping the D-link 192.168.1.1 from my boxes on the 192.168.1.x
> network.
>
> I don't want to have to add "route print" statements on all my boxes. I
> thought this is what routers were for...connecting different subnets?
>
> Thanks for your input!
>
> Thanks,
>
> The "Route Guy"

"q4n" <quest4nil@mytrashmail.com> writes:

>Hi Robert,

>Thanks for the reply!

>The reason I don't let DHCP do it's dirty deeds is that most of my
>boxes are servers or other test clients whose addresses I need to stay
>static.

>So, opening up my subnet mask is one solution, but in situations where
>widening the subnetmask is not desired, shouldn't my router be able to
>"route" from one subnet to the other?

It does. From the Wan to the Lan side of the box.


>I want my 192.168.10.100 to be able to send packets through 192.168.1.1
>(The D-link router) to get to 192.168.1.104 and other 192.168.1.x
>clients.

?? The problem is that you need to tell your system how to get to
102.168.1.1
route add -host 192.168.1.1 eth0
on each of the machines might work.
route add -network 192.168.1.0 netmask 255.255.255.0 gw 192.168.1.1 eth0
should do it.


>Can't I get the D-link to route this way without just opening my subnet
>mask?

>And does this mean I have to open the subnet mask on all clients and
>servers? The reason I ask is that, again, I've read that the router
>should be able to handle all of this without changing the clients as
>long as they are all plugged into the same router, because the router
>gets all the packets, but makes decisions about which to route based on
>it's own configured routing table.

>I thought I modified the routing table sufficiently with my
>> > Enable : Yes
>> > Destination IP 192.168.10.100
>> > Netmask : 255.255.255.0
>> > Gateway : 192.168.1.1
>> > Interface :LAN
>> > Metric : 1

>entry...but apparently not.

>Any direction on how to get the router to route without widening the
>subnet mask is appreciated!

>Sincerely,

>RG


>Robert Harris wrote:
>> q4n wrote:
>> > 8/5/2006, 1:23AM
>> >
>> > Hi,
>> >
>> > Thanks for taking the time to shine some light!
>> >
>> > I have a Linux Redhat 7.2 box on a 192.168.10.x network and I have
>> > clients that need to connect also connected to the same Dlink router
>> > which is at 192.168.1.1
>> >
>> > All my boxes are physically plugged into the D-link router so they are
>> > all on the same physical network.
>> >
>> > I heard that if all machines are on the same router, then all one has
>> > to do is add the odd man out network to the routing page, which I did:
>> >
>> >
>> > Enable : Yes
>> > Destination IP 192.168.10.100
>> > Netmask : 255.255.255.0
>> > Gateway : 192.168.1.1
>> > Interface :LAN
>> > Metric : 1
>> That would mean that packets for 192.168.10.100 are to be sent to
>> 192.168.1.1 which probably isn't what you want.
>>
>> If your 192.168.1.x and 192.168.10.x are on the same subnet, and there
>> aren't any othe 192.168.y.x on different subnets, then setting the
>> subnet mask to 255.255.0.0 is what you need to to.
>>
>> But why doesn't your Linux box have a 192.168.1.x address anyway? Why
>> don't you just let your router assign its IP address like everybody else's?
>>
>> Robert
>>
>> >
>> > My router is on 192.168.1.1
>> > Linux box is on 192.168.10.100
>> > clients on 192.168.1.100
>> >
>> > I don't want to be sloppy and change the subnet mask to 255.255.0.0
>> >
>> > [snip]

q4n wrote:
> Hi Route Guy, this is Route Guy:
>
> I got it to work, not by sloppily widening the subnet, but by adding
> the route the correct way on the D-link router. After I RTFM, whose
> directions are below, I changed the route from this:
> Enable : Yes
> Destination IP 192.168.10.100
> Netmask : 255.255.255.0
> Gateway : 192.168.1.1
> Interface :LAN
> Metric : 1
>
> to this:
>
> Enable : Yes
> Destination IP 192.168.10.0 (specifies entire 10.x network)
> Netmask : 255.255.255.0 (left same)
> Gateway : 0.0.0.0 (0's indicate all clients plugged into one/same
> router)
> Interface :LAN
> Metric : 1 (indicates there are no hops other than to d-link router)
>
> 192.168.1.x and 192.168.10.100 talk to each other now like it was high
> tea time at the All England Ladies Tea Club.
>
> Thanks for your input!
>
> Love,
>
> RG

Look: packets from one host on the subnet to another don't need to be
processed by the router. You can get your router to redirect packets on
the subnet if you want but that just means that each packet causes the
router to generate an extra one for no good reason.

If you keep the (IP address & netmask) the same for every member of a
subnet, then you can add other subnets to your network and use simple
routing decisions around it. If you don't, you will reach a situation
where each host has to know how to reach every other host individually.

If you want some IP addresses to be fixed (for servers), you can tell
your router about them and get the router to assign fixed IP addresses
to them for their given MAC addresses. That way the router, assuming it
is the nameserver on the network, knows the hostname of all the hosts
and the hosts can address one another by name without messing around
with hosts files.

>
>
>
> Adds a new route to the IP routing table or edits an existing route.
> Specifies whether the entry will be enabled or disabled.
> The IP address or network that the packets will be attempting to access
> Note: 192.168.1.0 with a Netmask of 255.255.255.0 means traffic will be
> routed to the entire 192.168.1.x network.
> Used to specify which portion of the Destination IP signifies the
> network
> trying to be accessed and which part signifies the host that the
> packets will
> be routed to
> Note: 255.255.255.255 is used to signify only the host that was entered
> in
> the Destination IP field.
> Specifies the next hop to be taken if this route is used. A gateway of
> 0.0.0.0
> implies there is no next hop, and the IP address matched is directly
> connected
> to the router on the interface specified: LAN or WAN.
> Specifies the interface, LAN or WAN, that the IP packet must use to
> transit
> out of the router when this route is used.
> The amount of hops it will take to reach the Destination IP or network.
> A
> hop is considered to be traffic passing through a router from one
> network to
> another. If there is only one router between your network and the
> Destination
> network, then the Metric value would be 1.
> q4n wrote:
>> 8/5/2006, 1:23AM
>>
>> Hi,
>>
>> Thanks for taking the time to shine some light!
>>
>> I have a Linux Redhat 7.2 box on a 192.168.10.x network and I have
>> clients that need to connect also connected to the same Dlink router
>> which is at 192.168.1.1
>>
>> All my boxes are physically plugged into the D-link router so they are
>> all on the same physical network.
>>
>> I heard that if all machines are on the same router, then all one has
>> to do is add the odd man out network to the routing page, which I did:
>>
>>
>> Enable : Yes
>> Destination IP 192.168.10.100
>> Netmask : 255.255.255.0
>> Gateway : 192.168.1.1
>> Interface :LAN
>> Metric : 1
>>
>> My router is on 192.168.1.1
>> Linux box is on 192.168.10.100
>> clients on 192.168.1.100
>>
>> I don't want to be sloppy and change the subnet mask to 255.255.0.0
>>
>> Shouldn't this work? But my Linux box at 192.168.10.100 can't ping my
>> D-link router at 192.168.1.1
>>
>> I could probably do a "route add" command on the Linux box to be able
>> to ping the D-link, but shouldn't the router, since it's on the same
>> physical network, see the ping from anything on it's network? Yes...it
>> should drop it from a different subnet...I know....but since I added
>> the route in the D-link routing table, shouldn't it not only see it but
>> route it and/or respond to it?
>>
>> I can ping the D-link 192.168.1.1 from my boxes on the 192.168.1.x
>> network.
>>
>> I don't want to have to add "route print" statements on all my boxes. I
>> thought this is what routers were for...connecting different subnets?
>>
>> Thanks for your input!
>>
>> Thanks,
>>
>> The "Route Guy"
>