VTP Configuration on GNS3 With NM
Transcript of VTP Configuration on GNS3 With NM
VTP Configuration on GNS3 with NM-16ESWVTP and VLAN configuration are different on a Router with NM-16ESW module to simulate a switch environment in GNS3. Here is a basic VTP server/client configuration with 3 vlans:
VTP Server Configuration:
SWT-01# vlan database
SWT-01(vlan)#vtp server
SWT-01(vlan)#vtp domain zenith
SWT-01(vlan)#vtp password mysecretkey
SWT-01(vlan)#vlan 100 name Management
SWT-01(vlan)#vlan 110 name Sales
SWT-01(vlan)#vlan 120 name Engineering
SWT-01(vlan)#exit
VTP Client Configuration
SWT-02# vlan database
SWT-02(vlan)#vtp client
SWT-02(vlan)#vtp domain zenith
SWT-02(vlan)#vtp password mysecretkey
SWT-02(vlan)#exit
Interface configuration:
There is no DTP on NM-16ESW so trunk links have to be manually configured. Another fact in GNS3 is that to prevent the possibility of any interface physical problems it is recommended to set "duplex" and "speed" manually on all Ethernet switch ports::
SWT-01(config-if)#switchport mode trunk
SWT-01(config-if)#speed 100
SWT-01(config-if)#duplex full
Follow the above configuration on any switch port with trunk function!
Some handy show commands for this scenario:
show vtp status
show vlan-switch brief
show interfaces trunk
show interfaces status
Setup a Cisco Switch Lab with GNS3The best way to have a Cisco switch lab is of course having the real devices at our hands but this is costly. Another option is to work with Cisco simulators like "PacketTracer", "RouterSim", or "ProfSIMS" but they are not real devices and what we see on the screen is just a simulation. There is another option
available called GNS3 which is a Cisco router hardware emulator and works great for setting up a Cisco router lab and everything works like the real world because you are providing the devices with real world IOSs.
GNS3 is a graphical user interface for the well know Dynagen/Dynamips Cisco router emulator. GNS3 can not offer any emulation for Cisco switches but since it supports NM-16ESW module we can use this in 2600/3600/3700 router series to build a switch lab although some switch configurations tasks are different and also lacks some switch features but its real! The best way to find about NM-16ESW configuration is the official cisco guide for EtherSwitch network module found at:
EtherSwitch Module Guide for 2600/3600/3700 Routers
I have tried NM-16ESW on Cisco 2691 and 3640 routers and it works fine. The NM-16ESW makes it possible to build a Cisco switch LAB on GNS3. To make it easier there are some facts and notes that should be kept in mind:
Some configuration commands on NM-16ESW module are different from Catalyst switches and the best way to find out about these differences is to refer to the "Configuration Tasks" section on Cisco EtherSwitch network module guide referred above
After physically connecting ports from two NM-16ESW modules they may still stay in the "notconnect" state. This is because of the speed and duplex negotiation problem so it is recommended to use manual speed and duplex on EtherSwitch ports. (Use "show interfaces status" command to see EtherSwitch ports status)
Creating VLANs on NM-16ESW is done the old way! Use the "vlan database" command in "global configuration mode" to enter VLAN configuration context.
Basically we use "show vlan brief" on catalyst switches to verifying VLAN configurations but on NM-16ESW we have to use "show vlan-switch brief" instead!
VTP configuration is only possible through the "vlan database" configuration context and is slightly different. Enter the vlan database configuration mode and try "vtp ?" to figure it out!
Spanning tree mode can not be changed! The only supported mode is PVST+ but it is possible to tune the features!
Does not support Port-Security!!!
Switching Commands not supported on NM-16ESW ModuleAs I mentioned before, I have a GNS3 lab on my laptop in which I'm using a Cisco 3725 with a NM-16ESW card.As I am progressing through the chapters, I'll post all the commands that are not supported by it, in comparison with a regular layer3 switch.
Here's the list:
"switchport trunk encapsulation isl""switchport trunk encapsulation negotiate""switchport mode dynamic desirable|auto""switchport nonegotiate""show interfaces vlan {vlan-id}""show vlan" --> "show vlan-switch""show vlan id {vlan-id}" --> "show vlan-switch id {vlan-id}"
"show vlan brief" --> "show vlan-switch brief""show vlan name {vlan-id}" --> "show vlan-switch name {vlan-id}""ip route-cache cef", under interface configuration level."spanning-tree guard root", under interface configuration level."spanning-tree bpduguard", under interface configuration level.
When I write the arrow sign ( -->) it means: here's the command that replaces it.