From: Tshon (tshon@xxxxxxxxxxx)
Date: Thu Mar 14 2002 - 19:58:01 GMT-3
Do you mind reposting the configs... I'm looking at the ones you have
and they seem to be missing some valueable info.
int ethernet0
ip address 172.16.43.2 255.255.255.0
R3 (token ring):
int tokenring0
ip add 172.16.43.3 255.255.255.0
source-bridge 10 4 200
source-bridge spanning
multiring ip
why are you using ring 200..... and where does the other router
reference 200 on it's interface...
or is 200 you virtual....
Then R4 (SR/TLB):
no ip routing
!
source-bridge ring-group 100
source-bridge transparent 100 200 5 1
!
int ethernet 0
bridge-group 1
!
int tokenring0
source-bridge 10 50 100
source-bridge spanning
multiring ip
The 50 is for the Bridge number... but you have 5 in ths transparent.
Brian Lodwick wrote:
> Are you talking about the configs I posted?
>
> The configs I posted were almost identical except instead of using
> multiring ip I used multiring all, and I changed the MTU on the
> Token-Ring portion to 1500 so that no packet ever reaches the ethernet
> side and is discarded because it exceeds ethernet's MTU size since
> Token-Ring's MTU is 4472, and the default MTU for most Cisco
> Token-Ring interfaces is 4464.
>
>>>> Brian
>>>
>
>
>> From: John Neiberger <neiby@ureach.com>
>> Reply-To: John Neiberger <neiby@ureach.com>
>> To: ccielab@groupstudy.com
>> Subject: SR/TLB for IP Discoveries (LONG)
>> Date: Thu, 14 Mar 2002 01:17:05 -0500
>>
>> Since I was temporarily fed up with staring at ipsec configs I
>> thought I'd take a crack at the SR/TLB stuff going on today. I
>> wasn't able to make this work using the configs posted today.
>> In fact, I can't figure out why the posted configs were working
>> at all. :-)
>>
>> I printed out three different docs from CCO and cross-
>> referenced that with examples from the archives to come up with
>> a working solution. Here is the scenario:
>>
>> R2 --- (eth) --- R4 --- (tr) --- R3
>>
>> Let's start with R4 since it's the most complex. The first
>> step is to configure SRB and transparent bridging:
>>
>> no ip routing
>> !
>> source-bridge ring-group 100
>> !
>> int to0
>> source-bridge 10 5 100
>> !
>> int e0
>> bridge-group 1
>> !
>> bridge 1 protocol ieee
>>
>> Then, configure SR/TLB to bridge between the two interfaces:
>>
>> source-bridge transparent 100 200 5 1
>>
>> In that config, the first number is from the source-bridge ring-
>> group statement. The second number is the virtual ring number
>> that identifies the transparent bridging domain to the SRB
>> domain. The third number is the bridge number taken from the
>> SRB config on the token ring interface. Finally, the fourth
>> number is the bridge-group number taken from the ethernet
>> interface config.
>>
>> At this point things won't be working just yet. On R2, the
>> ethernet-only router, we simply need to configure an IP
>> address. Then, we need to add an IP address to R3 that's in
>> the same subnet. Go ahead, try to ping...it won't work yet,
>> and here's where it starts to get a little tricky if you're
>> doing this with IP.
>>
>> On R4 you've configured SR/TLB which handles layer-two traffic
>> just fine but it doesn't know how to handle embedded layer
>> three addresses. To fix this, add the following:
>>
>> bridge 1 bitswap-layer3-addresses
>>
>> That's fairly straightforward, but things aren't going to work
>> yet. If you try to ping R2 from R3, the initial ARP will
>> fail. Why? Because the router needs to send an explorer and
>> it's not configured to do so. So, go to R3 and add the
>> following:
>>
>> int to0
>> source-bridge 10 4 200 (the 4 and 200 are irrelevant)
>> source-bridge spanning
>> multiring ip <------ important!
>>
>> Pings still won't work until you go back to the SR/TLB router
>> and add 'source-bridge spanning' and 'multiring ip'. At that
>> point, pings should succeed.
>>
>> With this solution there are no guarantees that all IP traffic
>> will work. In fact, this is configuration is probably a really
>> bad idea if you're running IP, but it at least sort of works.
>>
>> I broke this down into sections to show the steps I went
>> through to figure this out and make it work. Here are the
>> final working configs:
>>
>> R2 (ethernet):
>>
>> int ethernet0
>> ip address 172.16.43.2 255.255.255.0
>>
>> R3 (token ring):
>>
>> int tokenring0
>> ip add 172.16.43.3 255.255.255.0
>> source-bridge 10 4 200
>> source-bridge spanning
>> multiring ip
>>
>> R4 (SR/TLB):
>>
>> no ip routing
>> !
>> source-bridge ring-group 100
>> source-bridge transparent 100 200 5 1
>> !
>> int ethernet 0
>> bridge-group 1
>> !
>> int tokenring0
>> source-bridge 10 50 100
>> source-bridge spanning
>> multiring ip
>> !
>> bridge 1 protocol ieee
>> bridge 1 bitswap-layer3-addresses
>>
>> I currently have these exact configs on my routers, and here is
>> the result:
>>
>> R3#
>> R3#sho arp
>> Protocol Address Age (min) Hardware Addr Type
>> Interface
>> Internet 172.16.43.3 - 0000.30e2.cc0c SNAP
>> TokenRing0
>> R3#ping 172.16.43.2
>>
>> Type escape sequence to abort.
>> Sending 5, 100-byte ICMP Echos to 172.16.43.2, timeout is 2
>> seconds:
>> .!!!!
>> Success rate is 80 percent (4/5), round-trip min/avg/max =
>> 8/8/8 ms
>> R3#sho arp
>> Protocol Address Age (min) Hardware Addr Type
>> Interface
>> Internet 172.16.43.3 - 0000.30e2.cc0c SNAP
>> TokenRing0
>> Internet 172.16.43.2 0 0000.30b1.4bc1 SNAP
>> TokenRing0
>> R3#
>>
>> I sure hope I don't have to mess with this in the real lab, but
>> this little adventure was very enlightening. At least I think
>> I could get it working if I run into it when it counts. :-)
>>
>> Regards,
>> John
This archive was generated by hypermail 2.1.4 : Thu Jun 13 2002 - 10:57:09 GMT-3