Two IPs with different netmask on the same vlan

[gbs]

Can i add two ip in the same vlan?

My Black Diamond (BD8810) have his management interface on my vlan50 with netmask 255.255.0.0 (/16) and i have one Cisco that have the same vlan50 with netmask 255.0.0.0 (/8) but for other network.

I want to move the uplink of this other network to my BD. But the users of the other network need to check my "switch" SNMP via vlan50/8.

So, if i can use two VLAN50 ip address, one with /16 and other with /8 mask i can start to remove the cisco switch.

I know that i will have another problem in the future. That is to block all my traffic from VLAN50/16 to go to VLAN50/8 port. We already do this with the cisco switch, by blocking mac addresses.

[gbs]

Yes, they are overlapping. I want to use my 10G module of BD8810 for that. I will check that port specific vlan tag thing. Thanks.

[Erik_Auerswald]

Hi Gerson,

are the two "VLAN 50" networks overlapping? For example, 10.0.0.0/8 and 10.55.0.0/16 are overlapping networks. You cannot use a secondary IP address in this case. In fact, for overlapping IP networks you need different virtual routers (VRs), not just different VLANs.

If the networks are not overlapping, e.g. 10.0.0.0/8 and 172.20.0.0/16, then you can use a secondary IP address on VLAN 50. Please see the GTAC Knowledge article How to add secondary IP address on a VLAN.

To get around the problem of having the same VLAN ID for two networks with overlapping IP address ranges, you could add another switch in front of the BD to translate the VLAN tag, using e.g. port specific VLAN tags. Please see Does EXOS support Port-Specific VLAN Tag? and How to configure port specific tags.

Erik

[gbs]

It worked! Thanks 

[gbs]

Cos, i want to add two ip in the same vlan. And@Henrique told me to create another virtual route.