configure vlan on cisco 851

Hello All!

I regularly configure Vlans on Cisco router by using SUB interfaces like FastEthernet 1.200 .

Now i have to configure a vlan on a 851 with Advsecurity software. This command does not seem to be available? Is this a software restriction, or is it a different configuration method? I can see a command called VLAN, and i made a VLAN30 interface, but it seems to be UP/DOWN. Obviously i need to do some sort of layer 2 configuration also to get this interface up and running.

My question; how do i configure VLAN on this router, or is it not possible? config available upon request.

Who is Participating?
Don JohnstonConnect With a Mentor InstructorCommented:
Looks like you're one VLAN.  Sorry.

850's support only one VLAN. 870's on the other hand support four.

About a quarter of the way down:

Q. How many 802.1q VLANs can be configured on the built-in 4-port switch (Fast Ethernet 0-3)?    A. A maximum of four VLANs are supported on the Cisco 870 Series with the plus feature set (Advanced IP Services/Advanced Enterprise Services). The Cisco 850 Series only supports one 802.1q VLAN.

Don JohnstonInstructorCommented:
You need to create the VLAN in global config ("vlan 30"). Next, assign a port to be a member of the vlan in interface config mode ("switchport access vlan 30"). Then create the VLAN interface and assign an ip address.

conf t
vlan 30
int f0
 switchport access vlan 30
 no shut
int VLAN 30
 ip address
 no shut

Open in new window

johnnybrianAuthor Commented:
Yeah i figured as much, but it doesnt seem to work though. :(

Gw1(config)#vlan 30
Error on initialize VLAN database 1: VTP feature not yet initialized

% Unrecognized command

Can create Vlan30 interface correctly though.
interface Vlan30
 description AvayaDect
 ip address
 ip helper-address

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Don JohnstonInstructorCommented:
Can you post the output of a "show version" please.

johnnybrianAuthor Commented:
Cisco IOS Software, C850 Software (C850-ADVSECURITYK9-M), Version 12.4(15)T1, RE
Technical Support:
Copyright (c) 1986-2007 by Cisco Systems, Inc.
Compiled Wed 18-Jul-07 16:23 by prod_rel_team

ROM: System Bootstrap, Version 12.3(8r)YI4, RELEASE SOFTWARE

OutrupGw1 uptime is 12 weeks, 5 days, 2 hours, 45 minutes
System returned to ROM by reload at 14:19:33 CEST Thu Aug 14 2008
System restarted at 14:20:03 CEST Thu Aug 14 2008
System image file is "flash:c850-advsecurityk9-mz.124-15.T1.bin"

This product contains cryptographic features and is subject to United
States and local country laws governing import, export, transfer and
use. Delivery of Cisco cryptographic products does not imply
third-party authority to import, export, distribute or use encryption.
Importers, exporters, distributors and users are responsible for
compliance with U.S. and local country laws. By using this product you
agree to comply with applicable laws and regulations. If you are unable
to comply with U.S. and local laws, return this product immediately.

A summary of U.S. laws governing Cisco cryptographic products may be found at:

If you require further assistance please contact us by sending email to

Cisco 851 (MPC8272) processor (revision 0x200) with 49152K/16384K bytes of memor
Processor board ID FCZ112623HW
MPC8272 CPU Rev: Part Number 0xC, Mask Number 0x10
5 FastEthernet interfaces
128K bytes of non-volatile configuration memory.
20480K bytes of processor board System flash (Intel Strataflash)

Configuration register is 0x2102
Don JohnstonInstructorCommented:
Two questions/suggestions;

1) Can you try to put the switch/router in VTP transparent mode and see if that resolves the "VTP feature not yet initialized" message.

2) Which interface are you trying the "switchport" command on? If I remember correctly, It's only available on the first 4 interfaces (f0 - 3).
johnnybrianAuthor Commented:
transparent; done.

Gw1(config)#vla 30
Vlan can not be added. Maximum number of 1 vlan(s) in the database.

Tried to apply switchport to interfaces f0, f1 and f3. No go.
Don JohnstonInstructorCommented:
Now we're getting somewhere. You're only allowed one VLAN. Probably an IOS limitation. There are also a ton of software advisories on that image. I'd upgrade the IOS. "T" versions are always full of surprises.
johnnybrianAuthor Commented:
If I go to the software advisor, im oly allowed to downpload the Advsecurity feature set.  Is it a software limitation on this feature set? Because then im stuck.
johnnybrianAuthor Commented:
Thanks for that!
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