7750 collision /duplicate address

[adiltaleb]

Hi All,



I have 2x7750 connected trought a static AL and with 10Gbps from each 7750 to 8810 on separated vlan.



behind 2x7750 i have a multiple stack of 4500 connected with 2 trunk links to each 7750.



i manage 3 stp instances with mstp instance 0 default, 1 for data vlan and 2 for voice vlan.



first 7750 is root bridge for instance 0,1 and second 7750 is root bridge for instance 2.



i use vrrp betwen to 7750 for vlan interface.



the first 7750 is master for vlan 1 and data vlan and the second 7759 is master for voice vlan



the problem is on each switch 7750 and 4500 i have a collision with duplicate address for all vlan interfaces.



i have verifiy stp and all ip address are not duplicated on this network on all switch and i see the all instance are mapped correctly for each trunk link.



any one hase any idea about this problem?





Certified 3Com Enterprise LAN Exper/ IP Telephony VCX Expert

[aydinkocak]

Hello;

I thing your' users in network infected by virus.

This viruses affects are arp spoofing, arp poisoing, etc..



I suggest upgrade 3com 4500 switch to software 3.03.02,

this software include many function about arp attacks preventions and ip source guard function.



Following operation manual shows related configuration :

http://support.3com.com/documents/switches/4500/3Com_Switch_4500_Family_Operation_Manual_v3.3.2.pdf

AYDIN KOCAK,

3COM Enterprise LAN Expert ( Pre & Post Sales),

TippingPoint Security Engineer,

CCNA,CCDA, CCIE R&S Written