OK, For some reason, my first time of sending this reply got chopped, so
here it is again.
Brian, et al.,
Please Note the following:
***All I wanted to know was: Can the Loopback Interface be used to host a
complete subnet (and the Router make routing decisions with this inteface),
or is its functionality such that it will always respond like an interface
configured with a 255.255.255.255 mask, and 86 traffic not destined for IT
on the same subnet??
I'm not looking for someone to help me make a completely working config for
all routers in this implementation.
The idea is to do such:
!Interface FastEthernet0
! description Connected to PIX Outside Interface, and PIX Inside Interface
is subnet for Data traffic.
! Ip adress x.x.x.x 255.255.255.x
!Interface Loopback0
! description VoIP subnet with VoIP originating/terminating on this
Router... other hosts also placed on the same subnet at a later date, and
connecting via the Ethernet Port which connects to a switch that the other
hosts are also plugging into.
! Ip address 192.168.101.1 255.255.255.0
!Interface Serial0
! NO IP ADDRESS
! Encap Frame-Relay
!Interface Serial0.1
! description Connected to the Internet
! Ip address x.x.x.x x.x.x.252
! interface-dlci 16
!Interface Serial0.100
! description Connected to HQ over PVT FR for Voice traffic
! ip unnumbered loopback0
! interface-dlci 100
! {insert Map-Class Tag here}
!{Insert Route-Maps Here}
!{Insert Voice configuration here... a.k.a. Dial Peers}
!{Insert QoS config here... a.k.a. Map Classes}
!Router EIGRP 1750
!Network 192.168.100.0 >>Brian
""Mark Odette II"" wrote in message
[EMAIL PROTECTED]">news:[EMAIL PROTECTED]...
> OK, I'll make the question simpler.
>
>
> Can you use a loopback interface in the same respect that you would use an
> ethernet interface?
>
> Create the loopback: Interface Loopback0
> Assign it an IP with a /24 mask : ip address 192.168.10.1
> Configure the subnet assigned to the loopback interface to a routing
> process, such as EIGRP or RIP.
> Assign many other hosts on a LAN or a WAN an IP address that is in the
same
> subnet as the loopback interface.
> Replicate the above configuration on Router at other end of FR network.
> add subnet assigned to far-end routers' loopback interface to local EIGRP
> AS, or RIP; do the same on the far-end routers' config for the same EIGRP
AS
> or RIP configuration.
>
> And then, configure FR Subinterface with IP Unnumbered Loopback0, and
route
> traffic across the FR network, with the traffic orininating from either
the
> Router, or another host (if configuration above is legal) on the subnet
that
> is assigned to the Loopback interface.
>
> What I want to do, is configure a VoIP enabled router with a loopback
> interface assigned to 192.168.10.1, and several LAN hosts with the same
> subnet assignment, i.e., 192.168.10.2, .3, .4, etc., and a /24 subnet mask
> for all hosts including loopback interface.
> I then want to create and assign IP Unnumbered loopbackX to a FR P-to-P
> subinterface.
>
> Create EIGRP AS to route Subnets assigned to loopback interfaces on each
> respective router.
>
> Mirror image this configuration on the other end of the "wire" (FR
Network).
>
> Configure Dial-Peers with VOIP destinations pointing to the loopback
> interface of the peer router (other end of the FR Network).
>
> Is this Possible??
>
>
> The reason why I want to use Loopback interfaces, is because I plan to
> assign a separate subnet to the FastEthernet Interface, and don't believe
> that the use of the Secondary command will work, i.e., you can't specify
IP
> Unnumbered FastEthernet0 and have the Secondary IP address used.... ip
> unnumbered fastethernet0 will use the FastEthernets' Primary address,
which
> is not desired.
>
> The Primary Subnet assigned to the FastEthernet Interface will be NAT
> Translating with a PIX FW (PIX will be doing the NAT) to hit the Internet.
>
>
> For Topology description:
> Router HQ connects to internet on one subinterface, while connecting to 3
> remote offices on a private FR network on a second subinterface.
> Router Remote1 Will be connecting to the internet on one subinterface,
while
> connecting back to HQ on separate FR subinterface for VoIP over FR traffic
> only (no Data traffic)
> Router Remote2 will be doing the same as Remote1
> Router Remote3 will also be doing the same as Remote1
>
> ... So much for a simpler reply. :)
>
> Thanks in advance for everyones' comments.
>
>
>
> -----Original Message-----
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of
> Tshon
> Sent: Tuesday, March 12, 2002 11:44 PM
> To: [EMAIL PROTECTED]
> Subject: Re: Loopback Interfaces... [7:37933]
>
>
> What in the world is the question about, what are you trying to do.
> Ping the remote routers, they have a serial
> interface that you can ping, or the ethernet. Why do you need a
> loopback, what routing protocol are you
> running, where is a config? We can't figure out what you are talking
> about, we need your help to help you.
>
> Brian Lodwick wrote:
>
> >This has got to be the most confusing message I have ever read.
> >A loopback interface is just a virtual interface. It's not a real
interface
> >it's just a virtual interface you can create within the router, and you
can
> >create as many as you want.
> >The biggest reason someone would want to use a loopback interface would
be
> >for resiliency. If you build a certain session to the loopback interface
> >(BGP, DLSW...) and you have more than one path to reach this router the
> >session will not die if a certain interface dies.
> > ___________ ( )
> >------- r1 >>Brian
> >
> >
> >""Mark Odette II"" wrote in message
> >[EMAIL PROTECTED]">news:[EMAIL PROTECTED]...
> >
> >>Just when I thought I understood Loopback interfaces, I decided while
> >>redesigning a network, that I would use them.... but now I'm questioning
> >>
> >my
> >
> >>comprehension.
> >>
> >>Somebody clear the confusion for me- Please.
> >>
> >>
> >>This is what I'm wanting to do, but not sure if this is proper
> >>
> >utilization,
> >
> >>much less whether or not it will work:
> >>
> >>
> >>
> >>RouterHQ connecting to 3 Remote Routers (branch offices) via FR Pvt
> >>
> >Network
> >
> >>RouterHQ has 2 Ethernet Interfaces, but the Remotes Do NOT....They only
> >>
> >have
> >
> >>one.
> >>(I think without pause: "No Problem, I can just create a Loopback
> >>
> >interface
> >
> >>to take care of the other subnet.")
> >>
> >>The FR Pvt Network is only for Voice Traffic, while all data traffice
will
> >>be going out another interface that is using IP UnNumbered Interface
> >>FastEthernet0.
> >>
> >>Here is where my quandry lays. I can't create a Secondary address, as I
> >>believe the IP UnNumbered command will use the primary address on the
> >>Ethernet Interface.
> >>
> >>So, can I create a Loopback interface, and treate it like a Ethernet
> >>interface, as such that I can assign an IP to the Loopback interface,
but
> >>
> >it
> >
> >>have a /24 mask, and other devices on the local network can also be
keyed
> >>for the same subnet as the Loopback, making it where I can give the
> >>
> >command
> >
> >>IP UnNumbered Lo0 to a Serial SubInterface??
> >>
> >>I thought I could, but then got concerned when I hopped on CCO, and did
a
> >>lookup on Loopback interfaces, and read a blurb about traffic NOT
destined
> >>for the LoopBack Interface itself will be routed to 'ye old trashcan'
> >>
> >i.e.,
> >
> >>Null Interface.
> >>
> >>Somebody please tell me that I can send traffic from one end of the
> >>
> >circuit
> >
> >>to the other and have it destined for a node OTHER than the Loopback
> >>Interface with that node being on the same subnet as the Loopback
> >>
> >interface.
> >
> >>Thanks.
> >>
> >>Mark
Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=38285&t=38285
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