My CCIE 2008 Memo

Today, Jan 19th 2008

I have officially quit my job at IBM, took me half day to setup everything I need for now. My goal is to be ready for my 1st booking on April 15th.

I will try to post here as much as I can, I will treat this forum as my study memo, hope others to join me.

Alright, here I go.

Jan 19th 2008

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ITdude

Good luck, we will be following your journey.

Netstudent

Dang, you quit your job at IBM just to study for the CCIE? WOW! Good luck man.

Turgon

Netstudent wrote:

Dang, you quit your job at IBM just to study for the CCIE? WOW! Good luck man.

I know someone who worked for IBM years ago and he said it sucked!

Turgon

callmeall wrote:

Today, Jan 19th 2008

I have officially quit my job at IBM, took me half day to setup everything I need for now. My goal is to be ready for my 1st booking on April 15th.

I will try to post here as much as I can, I will treat this forum as my study memo, hope others to join me.

Alright, here I go.

Jan 19th 2008

All the best with your preparations and lab attempt. Time out of work should help a good deal, I wish you well!

GT-Rob

Look forward to following along.

If you don't mind, where in Canada did you work for IBM?

callmeall

Alright, guy

As you knew, I have started this CCIE study plan 2 weeks ago, I am digging on the Cats now.
Having a problem to understand VTP Pruning topic, did a search on cisco.com, and this is what I have found: http://www.cisco.com/en/US/docs/switches/lan/catalyst3550/software/release/12.1_12c_ea1/configuration/guide/swvtp.html#wp1035139

SHOW VTP STATUS
Switch#show vtp status
VTP Version: 2
Configuration Revision: 14
Maximum VLANs supported locally: 1005
Number of existing VLANs: 6
VTP Operating Mode: Server
VTP Domain Name: cisco
VTP Pruning Mode: Disabled
VTP V2 Mode: Enabled
VTP Traps Generation: Disabled
MD5 digest: 0xCF 0xE5 0xA7 0x2B 0x82 0xC9 0xA0 0xAA
Configuration last modified by 0.0.0.0 at 3-1-93 09:44:58
Local updater ID is 0.0.0.0 (no valid interface found)

But I still can't understand it in depth.

Is there a simpler example you guys out there could provide to me?

Any help will be nice at this point.

Thanks.

callmeall

I knew how to enable it, but that's about it!

Sw1(config)#vtp pruning

SHOW VTP STATUS
Sw1#show vtp status
VTP Version: 2
Configuration Revision: 14
Maximum VLANs supported locally: 1005
Number of existing VLANs: 6
VTP Operating Mode: Server
VTP Domain Name: cisco
VTP Pruning Mode: Enabled
VTP V2 Mode: Enabled
VTP Traps Generation: Disabled
MD5 digest: 0xCF 0xE5 0xA7 0x2B 0x82 0xC9 0xA0 0xAA
Configuration last modified by 0.0.0.0 at 3-1-93 09:44:58
Local updater ID is 0.0.0.0 (no valid interface found)

But how to see it actually works???

Help!!!

callmeall

Guys, below is what I have found on the cisco.com:

VTP Pruning
VTP pruning increases network available bandwidth by restricting flooded traffic to those trunk links that the traffic must use to reach the destination devices. Without VTP pruning, a switch floods broadcast, multicast, and unknown unicast traffic across all trunk links within a VTP domain even though receiving switches might discard them. VTP pruning is disabled by default.

VTP pruning blocks unneeded flooded traffic to VLANs on trunk ports that are included in the pruning-eligible list. Only VLANs included in the pruning-eligible list can be pruned. By default, VLANs 2 through 1001 are pruning eligible switch trunk ports. If the VLANs are configured as pruning-ineligible, the flooding continues. VTP pruning is supported with VTP version 1 and version 2.

Figure 12-1 shows a switched network without VTP pruning enabled. Port 1 on Switch 1 and Port 2 on Switch 4 are assigned to the Red VLAN. If a broadcast is sent from the host connected to Switch 1, Switch 1 floods the broadcast and every switch in the network receives it, even though Switches 3, 5, and 6 have no ports in the Red VLAN.

Figure 12-1 Flooding Traffic without VTP Pruning

http://www.cisco.com/en/US/i/000001-100000/45501-50000/45501-46000/45826.jpg

Figure 12-2 shows a switched network with VTP pruning enabled. The broadcast traffic from Switch 1 is not forwarded to Switches 3, 5, and 6 because traffic for the Red VLAN has been pruned on the links shown (Port 5 on Switch 2 and Port 4 on Switch 4).

Figure 12-2 Optimized Flooded Traffic with VTP Pruning

http://www.cisco.com/en/US/i/000001-100000/45501-50000/45501-46000/45827.jpg

Enabling VTP pruning on a VTP server enables pruning for the entire management domain. Making VLANs pruning-eligible or pruning-ineligible affects pruning eligibility for those VLANs on that device only (not on all switches in the VTP domain). See the "Enabling VTP Pruning" section. VTP pruning takes effect several seconds after you enable it. VTP pruning does not prune traffic from VLANs that are pruning-ineligible. VLAN 1 and VLANs 1002 to 1005 are always pruning-ineligible; traffic from these VLANs cannot be pruned. Extended-range VLANs (VLAN IDs higher than 1005) are also pruning-ineligible.

VTP pruning is not designed to function in VTP transparent mode. If one or more switches in the network are in VTP transparent mode, you should do one of these:

•Turn off VTP pruning in the entire network.

•Turn off VTP pruning by making all VLANs on the trunk of the switch upstream to the VTP transparent switch pruning ineligible.

To configure VTP pruning on an interface, use the switchport trunk pruning vlan interface configuration command (see the "Changing the Pruning-Eligible List" section). VTP pruning operates when an interface is trunking. You can set VLAN pruning-eligibility, whether or not VTP pruning is enabled for the VTP domain, whether or not any given VLAN exists, and whether or not the interface is currently trunking.

callmeall

Gt-ROB says:
If you don't mind, where in Canada did you work for IBM?

I was working for the Network Site in Toronto, where 14th Ave is.

Thanks.

Turgon

callmeall wrote:

I knew how to enable it, but that's about it!

Sw1(config)#vtp pruning

SHOW VTP STATUS
Sw1#show vtp status
VTP Version: 2
Configuration Revision: 14
Maximum VLANs supported locally: 1005
Number of existing VLANs: 6
VTP Operating Mode: Server
VTP Domain Name: cisco
VTP Pruning Mode: Enabled
VTP V2 Mode: Enabled
VTP Traps Generation: Disabled
MD5 digest: 0xCF 0xE5 0xA7 0x2B 0x82 0xC9 0xA0 0xAA
Configuration last modified by 0.0.0.0 at 3-1-93 09:44:58
Local updater ID is 0.0.0.0 (no valid interface found)

But how to see it actually works???

Help!!!

Cisco LAN Switching Chapter 12 VLAN Trunking Protocol pp567 VTP Pruning:Advanced Traffic Management has an example. If you are serious about the CCIE start hitting books like this one.

dtlokee

You can use the "show interface fa0/1 trunk" command (replace "fa0/1" with the one for the trunk you are pruning) to see what vlans if any have been pruned. This will show up in as a difference between the "vlans active in the management domain" and the "vlans active on the trunk" output.

callmeall

I think I have found a better way to slove this probelm that I am having for 2 days now!!!!!

lolololo, testing now, so excited!!! will post back for the detail of my result!

out!

callmeall

dtlokee says:
You can use the "show interface fa0/1 trunk" command (replace "fa0/1" with the one for the trunk you are pruning) to see what vlans if any have been pruned. This will show up in as a difference between the "vlans active in the management domain" and the "vlans active on the trunk" output.

dtlokee: I don't think "show interface fa0/1 or whatever here trunk" will show the pruning process. If anything will do the trick, it should be " show spanning-tree vlan #" the vlan # you shouldn't see there, cause it suppose to get pruned.

Well, anyways, I have some other thoughts in my mind now, gotta go right now to test it out, will let you know my findings...

cheers,

callmeall

Hi, everyone, here is what I found my testing result on the issue of “VTP Pruning”

I have builded a simple diagram looks like this:

On R1:
interface Ethernet0/0
description which is directly connected to Sw1 F 0/1
ip address 1.1.1.1 255.255.255.0
no shutdown

On R2:
interface Ethernet0/0
description which is directly connected to Sw1 F 0/2
ip address 2.2.2.2 255.255.255.0
no shutdown

On R3:
interface Ethernet0/1
description which is directly connected to Sw2 F 0/3
ip address 2.2.2.3 255.255.255.0
no shutdown

On R4:
interface Ethernet0/1
description which is directly connected to Sw2 F 0/4
ip address 1.1.1.4 255.255.255.0
no shutdown

My Sw1:
Vtp domain VTP_PRUNING
Vlan 11 name SITE_1
Vlan 12 name SITE_2
Vlan 100 name VLAN_100
Vlan 200 name VLAN_200
!
interface FastEthernet0/1
switchport access vlan 12
switchport mode access
!
interface FastEthernet0/2
switchport access vlan 13
switchport mode access

My Sw2:
interface FastEthernet0/3
switchport access vlan 13
switchport mode access
!
interface FastEthernet0/4
switchport access vlan 12
switchport mode access

as you can see, the idea is to make R1 (1.1.1.1) ping R4 (1.1.1.4) via VLAN 12 and R2 (2.2.2.2) ping-able to R3 (2.2.2.3) via VLAN 13…

Pay a closer attention to the following info:

Before I enable “vtp pruning”:

Sw1#show interfaces fastEthernet 0/23 trunk

Port Mode Encapsulation Status Native vlan
Fa0/23 desirable n-isl trunking 1

Port Vlans allowed on trunk
Fa0/23 1-4094

Port Vlans allowed and active in management domain
Fa0/23 1,12-13,100,200

Port Vlans in spanning tree forwarding state and not pruned
Fa0/23 1,12-13,100,200

Sw2#show interfaces fastEthernet 0/23 trunk

Port Mode Encapsulation Status Native vlan
Fa0/23 desirable n-isl trunking 1

Port Vlans allowed on trunk
Fa0/23 1-4094

Port Vlans allowed and active in management domain
Fa0/23 1,12-13,100,200

Port Vlans in spanning tree forwarding state and not pruned
Fa0/23 1,12-13,100,200

So far, NOTHING has pruned, that’s because I havn’t enable them yet. By default, the vtp pruning feature is disabled.

I then use “vtp pruning” to enabled on Sw1 and though BPDU packets, Sw2 will enable “vtp pruning” as well.

Now see the results again as the followings:

Sw1# show interfaces fastEthernet 0/23 trunk

Port Mode Encapsulation Status Native vlan
Fa0/23 desirable n-isl trunking 1

Port Vlans allowed on trunk
Fa0/23 1-4094

Port Vlans allowed and active in management domain
Fa0/23 1,12-13,100,200

Port Vlans in spanning tree forwarding state and not pruned
Fa0/23 1,12-13

And this sub-command as well:
Sw1#show interfaces fastEthernet 0/23 pruning

Port Vlans pruned for lack of request by neighbor
Fa0/23 100,200

Port Vlan traffic requested of neighbor
Fa0/23 1,12-13

Cheers,

P.S (in fact, dtlokee is correct, you can see the vtp pruning result with "show interface fa0/1 trunk" command, and I was thinking to use “show interface f 0/23 pruning” command. They are the samething anyways.

The result is showing me exactly what I want to see, and it’s so simple, but I guess sometimes, I just can’t 100% just memorize it according to the text book, I just have to proof it on my own, I don’t know, that’s just me.

Alright, I am out.

Have a nice day guys.

callmeall

Hi, everyone

Just like to update with ppl here, I think I have finished Switch both on 3550 and 3560 tomorrow, or at least I think I have covered most of the stuff in my study meterial.

I will be moving forward to RIP next week.

Thanks.