Cisco 2960G

We have a Cisco 2948G L3 switch that has five VLANs.  Is it possible to connect a new 2960G switches that will be part of those five VLANs?
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config will look like:
for both switches similar, but port numbers are different:

conf t
int gi0/1 - desired interface number
switchport trunk enq dot1q
switchport mode trunk
switchport trunk allowed vlans 1,2,3,4,5
desc link_to_2960G
CascadeDesignsAuthor Commented:
Will each vlans be able to talk to each other?  Currently, the 2948G is the one that does the job in order to pass traffic on each vlans.
it will continue to do so
2960G will only have access to vlans on 2948
you will need to assign ports of 2960G to appropriate vlans
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CascadeDesignsAuthor Commented:
Please see attached file.  If I added those two 2960G, and then I'm at the VLAN 30 ( that is connected on the (VLAN 20) using etherchannel where the is then connected on the main 2948G router using etherchannel as well, will I be able to talk to VLAN 10, 20, 40, 50 from VLAN 30.  I don't really want to buy a new 3750 L3 which will cost us too much.
you 2948G is L2 actually (
so in order to perform routing between vlans you need any L3 device, because 2960G is also L2 switch....

CascadeDesignsAuthor Commented:
Actually, it is an L3.  We've using this for at least six years now.  Here's the version.

Cisco Internetwork Operating System Software
IOS (tm) L3 Switch/Router Software (CAT2948G-IN-M), Version 12.0(7)W5(15d)  RELE
Copyright (c) 1986-2000 by cisco Systems, Inc.
Compiled Mon 05-Jun-00 16:16 by integ
Image text-base: 0x60010928, data-base: 0x605B8000

ROM: System Bootstrap, Version 12.0(7)W5(15a) RELEASE SOFTWARE

2948G-L3 uptime is 19 weeks, 1 day, 8 hours, 31 minutes
System restarted by power-on
System image file is "bootflash:cat2948g-in-mz.120-7.W5.15d.bin"

cisco Cat2948G (R5000) processor with 49152K/16384K bytes of memory.
R5000 processor, Implementation 35, Revision 2.1
Last reset from power-on
48 FastEthernet/IEEE 802.3 interface(s)
2 Gigabit Ethernet/IEEE 802.3z interface(s)
121K bytes of non-volatile configuration memory.
16384K bytes of processor board Boot flash (Read/Write)

Configuration register is 0x2101
so if it is L3, then it is doing routing for your vlans.
then 2960G will be used to provide additional ports...

please clarify your question.
CascadeDesignsAuthor Commented:
yes, that's correct.  The L3 is being used to route all our vlans.

For the two 2960G here is what I want.

On the first 2960G (reference pdf file attched last week), I want to create an etherchannel (G0/1 and G0/2) to form two full gigabit connection to the L3 switch.  All ports on this switch will be part of VLAN 20 except for the G0/23 and G0/24 which is the fiber connection that will be connected to the second switch.

The second switch will be connected using the same fiber port (G0/23 and G0/234) and will be etherchannelled too, and then all ports will be part of VLAN 30.

Will I still be able to talk to all VLANS within these two new switches?  What is the correct configuration for this?  I want to make sure that I will still have access to VLAN 10, 20, 40, and 50 from the second switch, and then access to VLAN 10, 30, 40, and 50 from the first switch.
the best practice here is to use VTP.

on 2948
enter command, VTP mode server

on 2960,
enter command: VTP mode client

then setup the port used to connect the 2 switches as trunks, with commands like:
switchport trunk encap dot1q
switchport mode trunk

Josh Kwok, MCSE, CCNP
CascadeDesignsAuthor Commented:
Well, from what Cisco was saying on the link below, the 2948G layer 3 switch will not support VTP.

Any other recommendation???
ooops, then in that case, for every VLAN you have on the 2948, just create the same VLANs on the 2960 with the "vlan xxx" command. This will make all the new 2960 switches aware of the VLANs.

Then just proceed on assigning vlans to port as you normal would (with "switchport access vlan xxx")

and make sure the ports connecting the switches together are still set as a trunk.

CascadeDesignsAuthor Commented:
Sounds good.  Though it still nice to have two ports etherchanneled to the L3 switch where all VLANS can pass through that channeled ports and talk to all VLANs.  But I guess there is really no other way aside from using five different trunk ports for each VLANs between the switches.  Is that possible or I have to upgrade to 3750 L3?

If it's not possible and I have to buy a 3750 then I'll take this solution.

Thanks for all your help!!
you can still do etherchannel, where ALL vlans will pass over the etherchannel.

just configure all the physical ports with the trunking commands above, then add in the channel groups command... something like:
 channel-protocol lacp
 channel-group 1 mode active

then on the port-channel interface, type in the trunking commands again:
 switchport trunk encap dot1q
 switchport mode trunk


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CascadeDesignsAuthor Commented:
I'll try this.  Thanks.
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