Switch VLAN's

[rraver]

Right now I got one VLAN that has multiple IP Address's on it. When I create another VLAN and take one of the subnets off of the first VLAN and switch it over. When I create the vlan and add the IP it is showing down. There for when I switch the machines over the the new VLAN they lose all communication, any ideas ?? I followed the configuration guide.

[msheik]

You might have done this, but just wants to reconfirm.. did you do the "no shutdown" under the vlan interface?

Thanks

MS

[Kevin Dorrell]

Is this on a layer 3 switch? I presume you have created an SVI for the VLAN (i.e. an interface vlan) but have you actually created the layer-2 vlan behind it, and are there any ports up in that VLAN?

Kevin Dorrell

Luxembourg

[rraver]

this is using a Cisco 4500 with two sup engines. I do the following with the configuration.

int vlan 1

no ip add 10.1.3.254 255.255.255.0 secondary

vlan 300

int vlan 300

ip add 10.1.3.254 255.255.255.0 secondary

no shut

then when I do a show int vlan 300 it shows up up so I go to my ports

int range giga 3/1 - 6

switchport access vlan 300

that's when it drops communication with them all.

When I do a show int vlan 300, it shows the traffic going out, but nothing ever coming in ???

[milan.kulik]

Hi,

one idea:

This might be an ARP problem.

Remember the ARP age timer is 4 hours by default.

So your PCs might have the old default gateway MAC address in their caches.

So I'd recommend clearing arp caches on all devices involved after the IP scope moved from one VLAN to another.

Regards,

Milan

[rraver]

I didn't think about that one, I will give it a try tonight and hope it works.

Thanks,

Rob