VLAN Project and Native VLAN

Is vlan2 trunked all the way back to the router? Can the router who owns vlan2's network ping the vlan2 devices? Can it (via an extended ping command) ping other vlans (1 & 3)? Can those other vlan interfaces ping vlans 2s? Sounds like a layer 3 issue due to a layer

Lastly, just because its a native VLAN does not mean that nothing else can route in or out, that is totally controlled by your configuration. In most configurations that I have seen, the native vlan is completely accessible by others.

Thanks for your reply.

My colleague is away for a while so this project needs to take a back seat. After I posted the last message, we found that after altering the default routes we had more joy.

We will check everything you mentioned in your post; I was very interested to read what you said about the native VLAN being accessible by others, and will draw my colleague's attention to this.

Many Thanks mark

completely accessible by others.

Check to see which switches support VTP, then configure them all into a single VTP domain, as much as posible and configure one single 3750 as the VTP Server (The rest as Client).

You can then manage the VLANs themselves centrally.

So, create a new VLAN 2 centrally.

If your 3750 also does your routing - easy peasy, just put the default GW for each subnet onto its VLAN interface on this switch.

Otherwise you need to trunk each VLAN to your router. Switch: switchport trunk encapsulation dot1q switchport mode trunk

Router: interface ethernet0/0 ip address

interface ethernet0/0.1 encapsulation dot1q 2 ip address

Now you need to trunk the VLANs to each switch.

Switch on each side: switchport trunk encapsulation dot1q switchport trunk native vlan 1 switchport trunk allowed vlan 1, 2 switchport mode trunk

If switches are daisy-chained off other switches, you need to ensure the VLAN required at the far end is trunked TO the intermediate switch, then FROM the intermediate switch to the next one in line. Needless to say, each switch needs the VLAN to exist on it, either by VTP or manually.

For ease of management, trunk your VLANs to the switches that need them. Alternatively, patching a switch into anbother switches port configured as "Sw Access VLAN 2" will mean that the switch will simply have VLAN2 as the default VLAN on all its Access ports. [ie, watch out for mis-matches opf VLANs between switchports - it'll work, but might confuse you]

Thanks for the help.

We think the problems were down to the VTP server needing a restart. All seems OK now. Your comments have certainly helped me to understand this subject a lot better, as it is my colleague who is the "Expert"

Many Thanks Mark