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Hello, EVE-NG community!

I am testing a bridge features in cisco routers using EVE-NG.

The network is shown on the picture (see attachment bridge.png).

It has two examples.

The first example has: VPC1_1, VPC2_1, VPC3_1, R_1.

The second example has: VPC1_2, VPC2_2, VPC3_2, R_2, S1_2, S2_2, S3_2.

The configuration of the router is shown on the right side of the picture.

The problem is in the second example when I try to ping VPC2_2 from VPC1_2.

The result is ARP flood.

Wireshark capture of R_2.e0/1 is shown on the picture (see attachment arp.png).

I am new to Cisco and EVE-NG.

Can anybody help me to understand why the first example work and the second doesn`t work?

How to fix arp flood in the second example?

I use the last version of EVE-NG and Cisco IOL for Routeres and Switches.

router bridge config issue only.
Just replicated your lab and all OK.



bridge irb
!
!
!
!
interface Ethernet0/0
no ip address
bridge-group 1
!
interface Ethernet0/1
no ip address
bridge-group 1
!
interface Ethernet0/2
no ip address
bridge-group 1
!
interface Ethernet0/3
no ip address
shutdown
!
interface BVI1
ip address 140.0.0.4 255.255.255.0
!
ip forward-protocol nd
!
!
no ip http server
no ip http secure-server
!
!
!
!
control-plane
!
bridge 1 protocol ieee
bridge 1 route ip
!


ADVICE, dont use such masks like /6
I used /24
UD

I have tried the suggested router config, also changed VPC netmask to 255.255.255.0, but result is the same - arp flood.

May be I am using bad cisco iol images? I have download it for free.

I also tried with dynamips images and vios images. I have download it for free too. But the result is the same - it doesn`t work for me.

no idea what are doing there,
but I used IOL 15.4.2T L3
and SW was L2 15.2 IRON
no issues at all

for all VPCS nodes Gateway must be router IP my lab its 140.0.0.4

Uldis (UD), thank you for your interest and help.

The behaviour of ARP flood seems to be unpredictable.

I think to reproduce ARP flood you have to try to ping each node from each node.

For example try ping: 140.0.0.2, 140.0.0.3, 140.0.0.4 from 140.0.0.1.

I have a shot video that show the problem.

Here is a link: https://yadi.sk/i/pmA82jtL3T5FN9

In video it is shown than I can ping 140.0.0.2, 140.0.0.3 from 140.0.0.1, I cannot ping 140.0.0.4 from 140.0.0.1.

And when I try to ping 140.0.0.1 from 140.0.0.4 I get ARP flood.

I use cisco IOL:

0086e5f41971bf35428c216a0ee6aabf L2-ADVENTERPRISEK9-M-15.2-IRON-20151103.bin
a3a45f36df542b7d3988391a12b2d980 L3-ADVENTERPRISEK9-M-15.4-2T.bin

No issues,
L3 is same,
but L2 is : try change L2 image

UD

The picture shows tree pings.

And can you ping a router?

yes, from any VPC and no flood
Router IP is 140.0.0.4
and no issues

Is it possible to test your L2 image?

I simplified the lab excluding Switches and have tested two configs of Router.

The first config has bridge without IP address:
no interface BVI1
no bridge 1 route ip

Its tcpdump of ping VPC6 from VPC5 is shown in apr1.png.

It seems to be OK.

The second config has bridge with IP address:
bridge 1 protocol ieee
bridge 1 route ip
interface BVI1
ip address 140.0.0.4 255.255.255.0

Its tcpdump of ping VPC6 from VPC5 is shown in apr2.png.

It seems to have a packet that produce ARP flood when we add Switches.

Can anybody explain me the difference beetwen two results?

My L2 and L3 images versions:

L2 Image
Cisco IOS Software, Linux Software (I86BI_LINUXL2-ADVENTERPRISEK9-M), Version 15.2(CML_NIGHTLY_20151103)FLO_DSGS7, EARLY DEPLOYMENT DEVELOPMENT BUILD, synced to FLO_DSGS7_POSTCOLLAPSE_TEAM_TRACK_DSGS_PI5
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2015 by Cisco Systems, Inc.
Compiled Wed 04-Nov-15 02:31 by mmen

L3 Image
Cisco IOS Software, Linux Software (I86BI_LINUX-ADVENTERPRISEK9-M), Version 15.4(2)T4, DEVELOPMENT TEST SOFTWARE
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2015 by Cisco Systems, Inc.
Compiled Thu 08-Oct-15 21:21 by prod_rel_team