What model router for VLAN communication

[1Drisnil]

I understand one would need a router of (RSM)Router Switch Module to allow seperate VLANs to commincate with each other. Question is, how does one begin to config the type of router one would need?



"...understanding "The Why" is half the battle!" - Anonymous.

 

[baddos]

What switches do you currently use?

 

[1Drisnil]

Baddos,

I use 2950 switches.

"...understanding "The Why" is half the battle!" - Anonymous.

 

[davemiller]

some switches have a layer 3 routing engine capability - refer to cisco.com, which could be used. You can use a third switch to physically connect two differently numbered vlans, but then you're effectively making them one vlan,
which can still work depending on your need.

 

[gunthnp]

that router does not do the vlan routing you need a router one port from each vlan goes to the router and then setup to route between these

the setup is a little different for each router

gunthnp from

http://wwww.advancedigitalsolutions.com

 

[baddos]

Personally, I'd pickup a 3550 switch and use that for your layer3. If you have a 2620 router lying around, you could setup an ISL trunk and do router on a stick. A 3550 would be a lot faster though.

 

[vince62s]

I have a similar problem

two catalyst 3548 with 2 VLANs, VLAN1 and VLAN2
each 3548 connected to a 4003 catalyst through trunking.

do I really need a router for non native VLAN communication (VLAN2) between 3548 #1 and #2 ?

same question for communication between 3548 and 4003 ?

VLAN1 is fine because native, what about VLAN2 ?

thanks

 

[baddos]

If you through a supervisor 3 in the 4003 switch, then it will do layer 3 routing.

VLANs can communicate with each other using just regular layer 2 switches (2950, 3548, 4003). A host on vlan 1 can't communicate to a host on vlan 2 without a router or a layer3 switch.

Example...

VLAN2 host on switch 3548 can communicate with VLAN2 host on 4003.

VLAN1 host on switch 3548 can't communicate with VLAN2 host on any switch and vs.

Image a VLAN as being a builing. When adding another switch with that vlan, it's like adding another room to your building. If your people need to leave your building (their vlan) and get to another building (another vlan), they need a road to get there (route). They take the road to drive down to the other building in their car (router or layer3 switch).

 

[vince62s]

I understand that but my problem is even more basic.

a host on VLAN 2 on a switch 3548 or 4003 cannot communicate with another host on the same VLAN 2 hooked to another switch.

when both hosts are on the same switch on VLAN2 everything is fine.

I checked VTP, trunking, everything looks fine between switches.

any idea?

 

[baddos]

vince62s... You don't have trunking setup properly then. A host on vlan 2 on your 3548 should be able to communicate with a host on vlan2 on the 4003. Can you post the interface configs for the links connecting the two switches?

 

[vince62s]

here is the configuration of the 3548 connected to the 4003
two ports 1 and 2 of 3548 connected to 43 and 44 of the 4003.

port 44 and 46 (VLAN 3) of the 3548 cannot communicate with ports 9 to 12 of the 4003.

thanks

*********************************************************
CONFIGURATION 3548
*********************************************************
!
version 12.0
no service pad
service timestamps debug uptime
service timestamps log uptime
service password-encryption
!
hostname CP2-2
!
enable secret 5 $1$6VRU$E9TNWjFN4y9rxdhmYdCxR0
!
!
!
!
!
!
ip subnet-zero
no ip domain-lookup
!
!
!
interface FastEthernet0/1
description Trunk vers 4003
duplex full
speed 100
port group 1
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface FastEthernet0/2
description Trunk vers 4003
duplex full
speed 100
port group 1
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface FastEthernet0/3
spanning-tree portfast
!
SAME FROM 0/3 TO 0/42
!
interface FastEthernet0/42
spanning-tree portfast
!
interface FastEthernet0/43
spanning-tree portfast
!
interface FastEthernet0/44
duplex half
speed 100
switchport access vlan 3
spanning-tree portfast
!
interface FastEthernet0/45
spanning-tree portfast
!
interface FastEthernet0/46
duplex half
speed 10
port monitor FastEthernet0/2
switchport access vlan 3
spanning-tree portfast
!
interface FastEthernet0/47
spanning-tree portfast
!
interface FastEthernet0/48
description Backup vers 3548-IP32
duplex full
speed 100
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface GigabitEthernet0/1
!
interface GigabitEthernet0/2
!
interface VLAN1
ip address 10.0.0.33 255.255.252.0
no ip directed-broadcast
no ip route-cache
!
snmp-server engineID local 000000090200000216FD6040
snmp-server community private RW
snmp-server community public RO
snmp-server chassis-id 0x17
!
line con 0
transport input none
stopbits 1
line vty 0 4
password 7 045902140720474B0014
login
line vty 5 15
password 7 01110F16530A0D0A2841
login
!
end

*****************************************************************
CONFIGURATION 4003
*********************************************************************

#system
set system name CC2-1
!
#frame distribution method
set port channel all distribution mac both
!
#vtp
set vtp domain NAME
set vtp v2 enable
set vtp pruning enable
set vlan 1 name default type ethernet mtu 1500 said 100001 state active
set vlan 2 name Internet type ethernet mtu 1500 said 100002 state active
set vlan 3 name DMZ type ethernet mtu 1500 said 100003 state active
set vlan 4 name mobi type ethernet mtu 1500 said 100004 state active
set vlan 1002 name fddi-default type fddi mtu 1500 said 101002 state active
set vlan 1004 name fddinet-default type fddinet mtu 1500 said 101004 state activ
e bridge 0x0 stp ieee
set vlan 1005 name trbrf-default type trbrf mtu 4472 said 101005 state active br
idge 0x0 stp ibm
set vlan 1003 name trcrf-default type trcrf mtu 4472 said 101003 state active pa
rent 0 ring 0x0 mode srb aremaxhop 0 stemaxhop 0 backupcrf off
!
#ip
set interface sc0 1 10.0.0.21/255.255.252.0 10.0.3.255

set interface sl0 down
set interface me1 down
!
#spantree
#vlan 1
set spantree priority 2000 1
!
#syslog
set logging level cops 2 default
!
#set boot command
set boot config-register 0x2
set boot system flash bootflash:cat4000.5-5-3.bin
!
#port channel
set port channel 2/1-4 1
set port channel 2/5-8 2
set port channel 2/9-12 3
set port channel 2/13-16 4
set port channel 2/17-20 5
set port channel 2/21-24 6
set port channel 2/25-28 7
set port channel 2/29-32 8
set port channel 2/45-48 13
set port channel 2/41-42 14
set port channel 2/43-44 15
set port channel 2/39 17
set port channel 2/40 18
set port channel 2/35-36 144
set port channel 2/37-38 146
set port channel 2/33-34 160
!
#http configuration
set ip http server enable
!
#module 1 : 0-port Switching Supervisor
!
#module 2 : 48-port 10/100BaseTx Ethernet
set vlan 2 2/1-7
set vlan 3 2/9-12
set vlan 4 2/22-24
set port auxiliaryvlan 2/17 2
set port speed 2/1-2,2/16,2/19-30 10
set port speed 2/3,2/5-7,2/9-15,2/17-18,2/33-48 100
set port duplex 2/1,2/3,2/5-6,2/10-14,2/33-48 full
set port name 2/1 Internet UUNET
set port name 2/2 Internet Colt
set port name 2/5 PIX1 Internet
set port name 2/6 PIX2 Internet
set port name 2/10 Free DMZ
set port name 2/11 PIX1 DMZ
set port name 2/12 PIX2 DMZ
set port name 2/13 PIX1 Intranet
set port name 2/14 PIX2 Intranet
set port name 2/33 Trunk vers 10.0.0.35
set port name 2/34 Trunk vers 10.0.0.35
set port name 2/35 Trunk vers 10.0.0.34
set port name 2/36 Trunk vers 10.0.0.34
set port name 2/37 Trunk vers 10.0.0.37
set port name 2/38 Trunk vers 10.0.0.37
set port name 2/39 Trunk vers 10.0.0.31
set port name 2/40 Trunk vers 10.0.0.31
set port name 2/41 Trunk 3548-2eme/1
set port name 2/42 Trunk 3548-2eme/1
set port name 2/43 Trunk 3548-2eme/2
set port name 2/44 Trunk 3548-2eme/2
set port name 2/45 Trunk 4003 1er
set port name 2/46 Trunk 4003 1er
set port name 2/47 Trunk 4003 1er
set port name 2/48 Trunk 4003 1er
set trunk 2/1 off dot1q 1-1005
set trunk 2/2 off dot1q 1-1005
set trunk 2/3 off dot1q 1-1005
set trunk 2/4 off dot1q 1-1005
set trunk 2/5 off dot1q 1-1005
set trunk 2/6 off dot1q 1-1005
set trunk 2/7 off dot1q 1-1005
set trunk 2/8 off dot1q 1-1005
set trunk 2/9 off dot1q 1-1005
set trunk 2/10 off dot1q 1-1005
set trunk 2/11 off dot1q 1-1005
set trunk 2/12 off dot1q 1-1005
set trunk 2/13 off dot1q 1-1005
set trunk 2/14 off dot1q 1-1005
set trunk 2/15 off dot1q 1-1005
set trunk 2/16 off dot1q 1-1005
set trunk 2/17 off dot1q 1-1005
set trunk 2/18 off dot1q 1-1005
set trunk 2/19 off dot1q 1-1005
set trunk 2/20 off dot1q 1-1005
set trunk 2/21 off dot1q 1-1005
set trunk 2/22 off dot1q 1-1005
set trunk 2/23 off dot1q 1-1005
set trunk 2/24 off dot1q 1-1005
set trunk 2/25 off dot1q 1-1005
set trunk 2/26 off dot1q 1-1005
set trunk 2/27 off dot1q 1-1005
set trunk 2/28 off dot1q 1-1005
set trunk 2/29 off dot1q 1-1005
set trunk 2/30 off dot1q 1-1005
set trunk 2/31 off dot1q 1-1005
set trunk 2/32 off dot1q 1-1005
set trunk 2/33 on dot1q 1-1005
set trunk 2/34 on dot1q 1-1005
set trunk 2/35 on dot1q 1-1005
set trunk 2/36 on dot1q 1-1005
set trunk 2/37 on dot1q 1-1005
set trunk 2/38 on dot1q 1-1005
set trunk 2/39 on dot1q 1-1005
set trunk 2/40 on dot1q 1-1005
set trunk 2/41 on dot1q 1-1005
set trunk 2/42 on dot1q 1-1005
set trunk 2/43 on dot1q 1-1005
set trunk 2/44 on dot1q 1-1005
set trunk 2/45 on dot1q 1-1005
set trunk 2/46 on dot1q 1-1005
set trunk 2/47 on dot1q 1-1005
set trunk 2/48 on dot1q 1-1005
set spantree portfast 2/1-4,2/7-8,2/15-32,2/39 enable
set port channel 2/33-36,2/39-48 mode on
set port channel 2/1-32,2/37-38 mode off
!
#module 3 empty
end
CC2-1> (enable)

 

[vince62s]

as a complement of the previous post,

the IP subnet I am using for VLAN 3 is 10.0.4.0 255.255.255.0 for which there is no IP nor route defined on the 4003

does it have something to do with the problem?

thanks