Hi,
I am currently trying to get a multicast source behind a NATting Cisco
router to work.
Setup:
- internal network: 172.30.1.0/24
- external IP: a.b.c.d
- Cisco 1401, IOS 12.1(8) IP Plus
- PIM-SM with an RP at 193.149.44.33 (via ATM0.32)
- IGMP in the LAN
If I have "receiver only" clients in the LAN, everything works fine
(like "listening to radio program").
Today I tried to setup vic to generate a video stream, and ran into
something that is definitely a NAT<->PIM interaction issue:
- Multicast source starts up
- local router generates mroute entry:
(172.30.1.153, 224.2.188.149), 00:18:38/00:02:59, flags: PCFT
Incoming interface: Ethernet0, RPF nbr 0.0.0.0
Outgoing interface list: Null
- local router sends register to RP, RP generates entry:
(172.30.1.153, 224.2.188.149), 00:19:09/00:01:14, flags: A
Incoming interface: FastEthernet0/0, RPF nbr 195.30.3.209
Outgoing interface list:
FastEthernet2/0, Forward/Sparse, 00:14:12/00:02:37
---> oops. As the source address is not NATted, the RP can't generate
PIM join messages into the proper direction, and thus my multicast
source isn't heard "outside".
This specific situation isn't covered in any documentation I could
find (so far), so I'm not sure whether this is "impossible to do"
or whether there is a trick in Cisco NAT to make it happen.
The router configuration in question (not IP relevant parts snipped,
global IP address changed) is:
ip multicast-routing
interface Loopback0
ip address a.b.c.d 255.255.255.255
interface Ethernet0
ip address 172.30.1.200 255.255.255.0
ip nat inside
ip pim sparse-dense-mode
interface ATM0
ip route-cache flow
interface ATM0.32 point-to-point
ip unnumbered Loopback0
ip nat outside
ip pim sparse-dense-mode
pvc 0/32
ubr 200
oam-pvc manage
encapsulation aal5mux ip
!
ip route 0.0.0.0 0.0.0.0 ATM0.32
ip pim rp-address 193.149.44.33
ip pim accept-rp 193.149.44.33
!
ip nat inside source list 170 interface Loopback0 overload
access-list 170 permit ip 172.30.1.0 0.0.0.255 any
(I have snipped the ip access lists for ATM0.32, but they do not log
anything, and the register message goes out, so that is not likely to
be related)
Soooo... any hints?
thanks!
gert
--
USENET is *not* the non-clickable part of WWW!
//www.muc.de/~gert/
Gert Doering - Munich, Germany gert@greenie.muc.de
fax: +49-89-35655025 gert.doering@physik.tu-muenchen.de
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