3745 with 36 port switch module

[Bluecrack]

I have a Cisco 3745 with a 36 port switch module. Is it possible to create multiple vlans and assign the various switch ports to the VLANs?

If so is it as simple as:

int vlan10
ip address 10.1.10.1 255.255.255.0
int vlan20
ip address 10.1.20.1 255.255.255.0
int fa4/0
switchport access vlan 10
int fa4/1
switchport access vlan 20

 

[vipergg]

Yes you can . You will have to create the layer 2 vlans in the vlan database . Once you do this and save you casn create the layer 3 side and assign your ports into the vlans.

 

[Bluecrack]

Thanks vipergg. I've done that already and cannot get the line protocol to come up. I was hoping there was another quick config change I needed to make.

Is there anything that needs to be done to allow the switchport to communicate to the VLAN across the backplane?

 

[vipergg]

You will need at least one active device on your ports before the layer 3 side will come up , this is normal behavior.

 

[Bluecrack]

vipergg,

Thanks for your help. My coworker most graciously pointed out the error of my ways in one word - crossover [cable].

Off to bang my head on the wall for missing the most obvious.

 

[Bluecrack]

vipergg

I'm back with more confusion. I've got connectivity to the above setup but having problems with pinging through.

Background.
We have a Cisco 2900XL switch with multiple separate VLANs. There is no communication between the VLANs no do we necessarily want any. I am plugging the Cisco 3745 into this switch and using it to convert POTS calls to VoIP (SIP) calls and need to route these calls to one of the VLANS on the switch. Since the two FastEthernet ports on module 0 are used for other purposes, I planned to use the completely empty 36 port FastEthernet module in slot 4 to do my bidding.

So now I
- have my crossover cable in place
- added a vlan to the 3745 switch's vlan database
- added interface vlan34 with IP addresses
- assigned fa4/0 to vlan34

So the problem is when I ping from the router to one of the devices connected to the 2900XL switch, the ping fails but the remote end device's MAC address shows up in the mac address table. It seems like broadcasts are making it out of fa0/4 and into fa0/4 but directed IP traffic does not. Is there something that needs to be done to bind the fa port to vlan34?

Here are the relevant sections of the config:

interface FastEthernet4/0
switchport access vlan 34
duplex full
speed 100
!
interface Vlan34
ip address 192.168.34.2 255.255.255.0
no ip redirects
no ip unreachables
no ip proxy-arp
!

From VLAN Database
VLAN ISL Id: 34
Name: VLAN0034
Media Type: Ethernet
VLAN 802.10 Id: 100034
State: Operational
MTU: 1500

 

[ADB100]

I am not sure if this is against any forum rules? If it is then don't ban me just delete the post and tell me....
But if anyone wants one of these modules (NMD-36-ESW) then I have one that I was going to list on eBay. It was surplus to requirements for a project and almost ended up in a skip....

Andy

 

[burtsbees]

Do you have 802.1Q as the trunking protocol on the 2900 or ISL, like you have on the 3745? ISL and 802.1Q do not work together. Please post a sh run from the 2900 if you are unsure.

Burt

 

[vipergg]

If you have a 2924 and you just want to be able to talk to it on vlan 34 just default the 2924 to factory defaults and it should work . seeing that you hardcoded the 3745 port you would have to hardcode the 2924 connecting port to 100/full . If you want to manage the switch then you have to apply an ip address out of the vlan 34 address range and apply it under interface vlan 1 and set the default gateway to 192.168.34.2 .

 

[vipergg]

You might be better to post the 2924 config , if you have multiple separate vlans and they have to stay then you will have to trunk to the 2924 unless those subnets are not to be routed .

 

[Bluecrack]

Here's the config for the 2924 swithport

interface FastEthernet0/7
description voip-rt_34
duplex full
speed 100
switchport access vlan 34
!

interface VLAN34
ip address 192.168.34.51 255.255.255.0
no ip directed-broadcast
no ip route-cache
!

voip-mon-sw-1#show vlan id 34
VLAN Name Status Ports
---- -------------------------------- --------- -------------------------------
34 VLAN0034 active Fa0/1, Fa0/2, Fa0/3, Fa0/4,
Fa0/7, Fa0/9, Fa0/12

VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
---- ----- ---------- ----- ------ ------ -------- ---- -------- ------ ------
34 enet 100034 1500 - - - - - 0 0

 

[vipergg]

Is f0/7 the uplink to the router ? if not please post config of the uplink port on the 2924 .

 

[vipergg]

Better yet post the whole 2924 config if possible . At the very least post the uplink port config and a "show vlan" command.

 

[Bluecrack]

fa0/7 is the uplink port.

It don't necessarily want to trunk multiple vlans between switches. Basically I need a group of ports on the this switch to talk to vlan34 on the router. I could just as easily use this whole switch in VLAN1 and connect it to the switchport on the router. From there though, I need that port on the router to be partof VLAN 34 on the router so I can gain access to the 192.168.34.2 IP address because that's what the voice calls will come through as ... in theory.

What I really need is fa0/3 but this router only has 2 Fa0/x ports. I'm trying to make fa4/0 behave as another router port.

 

[vipergg]

If all you need is vlan 34 on the 2924 then default everything to vlan 1 on the 2924(write erase then reload) give it a address from the vlan 34 address range on the router , point the defualt gateway on the switch to the vlan 34 router address and this should give you access to vlan 34 on the 2924. Also make sure any device on the 2924 , the nic default gateway is pointed to the vlan 34 router address . From what I can tell from your previous post the router config looks correct.

 

[Bluecrack]

That's exactly what I thought too and basically what I did. The only exception is that I have the 2924 VLANed because I have two completely seperate networks I need to support but only have one switch. For consistency sake I've named them VLAN 33 and 34.

But aside from that the 2924 is basically a dumb switch connected to a port on the router. It's almost like the SVI on the router isn't working correctly.

 

[vipergg]

Are you routing both vlans , if so then your uplink has to be a trunk on both ends , if you are just trying to route vlan 34 then just making a layer 2 vlan for 34 on the 2924 and then plugging it back to the router should work . The ip address on the switch is just to manage the switch and nothing else. Nic default gateway would be pointed to the router interface address for vlan 34 . Also if you are trying to ping from the router or switch to an attached pc make sure the pc firewall is off otherwise it will fail .