Re: Native VLAN?

this is just a CDP issue using the vlan id you have set with the 'switchport
access vlan' if you look at the 'show int f0/2 switchport' does it still say
native vlan is 1? or 502? and it does not matter cause not a trunk...

you will see it says one, but CDP sends the it as 502 if you look on the
wire you will see this in the CDP packet...

but it is not a trunk so no tags will be on the packet, so it will pass
traffic between the two ports, but CDP will just complain about it...

CDP packet capture from wireshark:

No. Time Source Destination Protocol
Info
      9 13.440000 c4:00:12:b8:f1:0f CDP/VTP/DTP/PAgP/UDLD CDP
Device ID: R1 Port ID: FastEthernet1/15

Frame 9: 350 bytes on wire (2800 bits), 350 bytes captured (2800 bits)
IEEE 802.3 Ethernet
Logical-Link Control
Cisco Discovery Protocol
    Version: 2
    TTL: 180 seconds
    Checksum: 0x7884 [correct]
        [Good: True]
        [Bad: False]
    Device ID: R1
        Type: Device ID (0x0001)
        Length: 6
        Device ID: R1
    Software Version
        Type: Software version (0x0005)
        Length: 253
        Software Version: Cisco IOS Software, 3700 Software
(C3745-ADVENTERPRISEK9-M), Version 12.4(15)T14, RELEASE SOFTWARE (fc2)
                          Technical Support:
http://www.cisco.com/techsupport
                          Copyright (c) 1986-2010 by Cisco Systems, Inc.
                          Compiled Tue 17-Aug-10 12:55 by prod_rel_team
    Platform: Cisco 3745
        Type: Platform (0x0006)
        Length: 14
        Platform: Cisco 3745
    Addresses
        Type: Addresses (0x0002)
        Length: 8
        Number of addresses: 0
    Port ID: FastEthernet1/15
        Type: Port ID (0x0003)
        Length: 20
        Sent through Interface: FastEthernet1/15
    Capabilities
        Type: Capabilities (0x0004)
        Length: 8
        Capabilities: 0x00000029
            .... .... .... .... .... .... .... ...1 = Is a Router
            .... .... .... .... .... .... .... ..0. = Not a Transparent
Bridge
            .... .... .... .... .... .... .... .0.. = Not a Source Route
Bridge
            .... .... .... .... .... .... .... 1... = Is a Switch
            .... .... .... .... .... .... ...0 .... = Not a Host
            .... .... .... .... .... .... ..1. .... = Is IGMP capable
            .... .... .... .... .... .... .0.. .... = Not a Repeater
    VTP Management Domain:
        Type: VTP Management Domain (0x0009)
        Length: 4
        VTP Management Domain:
    Native VLAN: 502
        Type: Native VLAN (0x000a)
        Length: 6
        Native VLAN: 502
    Duplex: Full
        Type: Duplex (0x000b)
        Length: 5
        Duplex: Full

--
Garry L. Baker
"There is no 'patch' for stupidity." - www.sqlsecurity.com
On Thu, Sep 30, 2010 at 9:47 AM, hopalong <ccieangel2_at_googlemail.com> wrote:
> Hi
>
> I have two access ports connected to one another one is configured as
>
> interface FastEthernet0/2
>  duplex full
>  speed 100
>  switchport access vlan 502
>
> and the other as
>
> switchport mode access 162
>
> This link seems to be working fine! The only clue I have is that the cdp
> neighbor entry at the vlan 502 end says that the native vlan is 162.
>
> No native vlans are defined. How is this working?
>
> Thanks
>
>
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