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IPV6 intervaln routing on swicthes

hi expert,

i am trying to setup a lab for someone where 2 switches are connected over the trunk, one swicth is working is layer 3 switch and 2nd as layer 2. both swicthes are 3750 wth ip services images

i configured 2 vlan let say 5 and 6 and configured ipv4 and ipv6 addresses

i coneceted to syetms one in vlan 5 on one 1st switch and 2nd on 2nd switch in vlan 6

from first pc i am able to ping vlan interface 5 and vlan interface 6 and same from the 2nd pc

but whenever i want to ping these 2 systems with each other i am not getting any responce

i have already enabled IPV6 on both swicthes with following commnad on layer 3 switch

ip routing

ipv6 unicast routing

sdm prefere dual-ipv4-and-ipv6 default

interface vlan 5

ip address

ipv6 address 2001:cc1e:1:2323::1/64

one system is configured with above subnet and gateway and ping both interface vlan

interface vlan 6

ip address


2nd system configured wth above ipv6 subnet and gateway and ping both interface vlan ip but not the 2nd pc connected in vlan 5

2nd switch is working at layer 2 switch with trunk configured with layer 3 swcitch

please suggest

Zahid Fayyaz


Re: IPV6 intervaln routing on swicthes


If you are able to ping both IPv6 addresses 2001:cc1e:1:2323::1 and 2001:cc1e:1:2424::1 from both hosts but not eachother, then you need to check the PC. Usually it is the firewall which is blocking the ICMP packet.

Also, have you rebooted the switches? When you change the SDM template with "sdm prefer", it requires a reload to take effect.


Community Member

Re: IPV6 intervaln routing on swicthes

Thanks Mihanlin

i tested in other swicthes enviornment where it is running fine

yes i agree with you the problem could be on PC side but we diabled both firewalls on both PC

even then PCs are uanble to communicate

above all i rebooted the swicthes to take effect of SDM

i ll check it again on weekend

thanks for ur help

Community Member

Re: IPV6 intervaln routing on swicthes

I think you need to have Advanced IP Services to do IPv6 routing.


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