How to Bridge two networks(newbie) 1

[lloydie2]

I am a newbie to cisco routers, so please forgive my ignorance.
I currently have a bridged network using old 3com 532s routers. One of these has packed in, so I am going to replace both of them with cisco 1700's. These will be connected to 256kb lease line from BT.
Can someone point me in the right direction to set these up so the the networks are bridged? Currently the network looks like the following

site A
application server = 194.64.21.21
router 1 LAN ip = 194.64.21.230
route 1 WAN ip = ???.???.???.???

Site B
client PC = 192.64.21.20
router 2 LAN ip = 194.64.21.231
router 2 WAn ip = ???.???.???.???

this is all the information I could get of the 3com router.

 

[ADB100]

Since you are bridging then the IP addresses assigned to interfaces are used only to manage the routers so are all in the same IP network (194.64.21.0/24). In a routed environment each interface is usually in its own subnet, this is probably the preferred way to go but would require you to make changes on hosts etc. The simple solution is to just set up bridging:

!
no ip routing
!
bridge 1 protocol ieee
!
interface Ethernet0
bridge-group 1
!
interface Serial0
bridge-group 1
!

This part of the configuration would be identical on each router (bridge?). You could assign an IP address to an interface so it could be remotely managed, this is done in the format:

interface XXX
ip address 194.64.21.21 255.255.255.0

HTH

Andy

 

[lloydie2]

Thanks for that Andy. Is there any specific settings for serial0 to set it to 256kb.

 

[ADB100]

I assume the circuit is provided by a carrier? If so it will provide it's own clocking and the routers (with the correct cables of course) will simply use the received clock on the circuit. You should really set the bandwidth command on the interface but this has NOTHING to do with the actual clock rate;it is used for statistics and also some routing protocol's (such as OSPF) use the bandwidth to determine the metric a link has.

If you are using back-to-back cables (DCE-to-DTE) between Cisco routers then you need to generate a clock on the DCE end of the link, this is done with the 'clock rate xxxx' command. It looks like you have WAN circuits (probably X.21/V.11) so your provider generates the clocks.

HTH

Andy

 

[lloydie2]

Andy,
I have tried your settings, but I do not seen to be able to ping any IP addresses across the link. BTW the routers are 1603 with 11.2 software.
This is the currrent config for each site.

---------------------------------------


Using 682 out of 7506 bytes
!
version 11.2
no service password-encryption
no service udp-small-servers
no service tcp-small-servers
!
hostname cem-access02
!
enable secret 5 $1$L0MD$GaS7rJYi.6XBLg2spjq7.1
enable password meghan
!
no ip routing
!
interface Ethernet0
ip address 194.46.21.231 255.255.255.0
no ip route-cache
no logging event subif-link-status
bridge-group 1
!
interface Serial0
no ip address
no ip route-cache
no logging event subif-link-status
bridge-group 1
!
interface BRI0
no ip address
no ip route-cache
no logging event subif-link-status
shutdown
!
no ip classless
snmp-server community public RO
bridge 1 protocol ieee
!
line con 0
line vty 0 4
password meghan
login
!
end
----------------------------------


The following is a show on serial0

----------------------------------
Serial0 is up, line protocol is up
Hardware is QUICC Serial
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec, rely 255/255, load 1/255
Encapsulation HDLC, loopback not set, keepalive set (10 sec)
Last input 00:00:07, output 00:00:01, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0 (size/max/drops); Total output drops: 0
Queueing strategy: weighted fair
Output queue: 0/1000/64/0 (size/max total/threshold/drops)
Conversations 0/2/256 (active/max active/max total)
Reserved Conversations 0/0 (allocated/max allocated)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
7522 packets input, 180227 bytes, 0 no buffer
Received 349 broadcasts, 0 runts, 0 giants, 0 throttles
62 input errors, 0 CRC, 62 frame, 0 overrun, 0 ignored, 0 abort
5169 packets output, 421794 bytes, 0 underruns
0 output errors, 0 collisions, 148 interface resets
0 output buffer failures, 0 output buffers swapped out
12 carrier transitions
DCD=up DSR=up DTR=up RTS=up CTS=up
-------------------------------------------------

Any Ideas.

Lloyd

 

[ADB100]

I know the configuration will work as I have just tested it on a couple of 2500-series routers. What do you see when you issue the command 'show bridge 1'? You should see the bridging table and what MAC addresses are seen on each bridged interface.

Andy

 

[lloydie2]

Unfortunately I have had to leave the routers on site. and have no access to them until tommorrow. There may also be a problem with the way the routers are booting up (as of question 1103039)

 

[lloydie2]

Doh. I was trying to ping from the console port. When I tried it from the ethernet port, all is OK. Tested the other apps and they were OK too.
Thanks for your help Andy.