IPv6Freelys LAN Configuration
From Internetworkpro
Contents |
[edit] Overview
[edit] Problems
Our network is currently completely flat. ~120 access switches ~6 distribution switches and 1 core switch, which is the one and only layer 3 device on our network. Luckily for the most part we have no end-to-end VLANs - VLANs have been assigned per-building. However this poses two problems:
- We have ~124 VLANs in the core configuration. This is awfully close to the 128 VLAN limit when using PVST+. We've actually hit the 128 VLAN limit and it wasn't pretty.
- We have gotten lazy, and because of the VLAN shortage, we have started assigning VLANs to ports in buildings for which they don't belong. This is obviously bad.
- Our core route table is disgusting. While it's not that big per se, it's a whole lot bigger then it needs to be for such a small campus.
- There is no possibility for summarization using our current IP addressing scheme. The current scheme is 172.function.building.0/24, where function could be faculty/staff, printers, labs, wireless, voice, etc.
- We have terrible daisy-chaining of access switches going on. I'm not sure if it was to save costs on fiber, or whether the previous administators didn't understand STP diameter, or proper design - I'm not sure. At some points we have a STP diameter of as large as 12.
[edit] Solutions
There are two options for fixing our VLAN issue:
- Deploying MST
- Create a routed distribution layer
While #1 would work, it makes sense to simply solve the problem at its root - poor design.
[edit] Example Building
[edit] Diagram
[edit] Configurations
SW-KELCE-CORE:
!
hostname sw-kelce-core
!
spanning-tree mode rapid-pvst
spanning-tree extend system-id
!
vlan 131
name "LEGACY - Kelce OIS"
!
vlan 2021
name TRANSIT-21
!
interface Gi3/15
description *** LINK TO BUILDING 21 ***
switchport
switchport trunk encapsulation dot1q
switchport mode trunk
switchport nonegotiate
!
interface vlan 131
description LEGACY - Kelce OIS
ip address 172.16.31.1 255.255.255.0
!
int vlan 2021
description TRANSIT-21
ip address 10.0.21.1 255.255.255.252
ip ospf authentication message-digest
ip ospf message-digest-key 1 md5 <key>
ip ospf network point-to-point
!
router ospf 100
router-id 10.0.0.2
log-adjacency-changes detail
auto-cost reference-bandwidth 100000
passive-interface default
no passive-interface Vlan2021
network 10.0.21.0 0.0.0.3 area 0
default-information originate metric-type 1
!
SW-RECCENTER-DIST
!
hostname sw-reccenter-dist-1
!
vtp mode transparent
!
ip routing
!
spanning-tree mode rapid-pvst
spanning-tree extend system-id
!
vlan 121
name Faculty/Staff
!
vlan 131
name "LEGACY - Kelce OIS"
!
vlan 221
name Printers
!
vlan 321
name Labs
!
vlan 421
name Public-Access
!
vlan 521
name Wireless
!
vlan 621
name Dorms-Registered
!
vlan 721
name Dorms-Unregistered
!
vlan 821
name Voice
!
vlan 921
name Management
!
vlan 1021
name Public
!
vlan 2021
name TRANSIT-21
!
interface GigabitEthernet1/0/1
description *** LINK TO SW-KELCE-CORE-1 ***
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 131,2021
switchport mode trunk
switchport nonegotiate
!
interface GigabitEthernet1/0/11
description *** LINK TO SW-RECCENTER-1ST-1 ***
switchport trunk encapsulation dot1q
switchport mode trunk
switchport nonegotiate
!
interface GigabitEthernet1/0/12
description *** LINK TO SW-RECCENTER-2ND-1 ***
switchport trunk encapsulation dot1q
switchport mode trunk
switchport nonegotiate
!
interface Vlan1
no ip address
shutdown
!
interface Vlan121
description Faculty/Staff
ip address 10.21.10.1 255.255.254.0
ip helper-address 172.16.33.18
ip helper-address 172.16.33.19
!
interface Vlan221
description Printers
ip address 10.21.20.1 255.255.254.0
ip helper-address 172.16.33.18
ip helper-address 172.16.33.19
!
interface Vlan321
description Labs
ip address 10.21.30.1 255.255.254.0
ip helper-address 172.16.33.18
ip helper-address 172.16.33.19
!
interface Vlan421
description Public-Access
ip address 10.21.40.1 255.255.254.0
ip helper-address 172.16.33.18
ip helper-address 172.16.33.19
!
interface Vlan521
description Wireless
ip address 10.21.50.1 255.255.254.0
ip helper-address 172.16.33.18
ip helper-address 172.16.33.19
!
interface Vlan621
description Dorms-Registered
ip address 10.21.60.1 255.255.254.0
ip helper-address 172.16.33.18
ip helper-address 172.16.33.19
!
interface Vlan721
description Dorms-Unregistered
ip address 10.21.70.1 255.255.254.0
ip helper-address 172.16.33.18
ip helper-address 172.16.33.19
!
interface Vlan821
description Voice
ip address 10.21.80.1 255.255.254.0
ip helper-address 172.16.33.18
ip helper-address 172.16.33.19
!
interface Vlan921
description Management
ip address 10.21.90.1 255.255.254.0
!
interface Vlan1021
description Public
ip address 216.21.102.193 255.255.255.192
ip helper-address 172.16.33.18
ip helper-address 172.16.33.19
!
interface Vlan2021
ip address 10.0.21.2 255.255.255.252
ip ospf authentication message-digest
ip ospf message-digest-key 1 md5 <key>
!
router ospf 100
router-id 10.0.21.2
log-adjacency-changes
auto-cost reference-bandwidth 100000
area 21 range 10.21.0.0 255.255.0.0
passive-interface default
no passive-interface Vlan2021
network 10.0.21.0 0.0.0.3 area 0
network 10.21.0.0 0.0.255.255 area 21
!
SW-RECCENTER-1ST-1
!
hostname sw-reccenter-1st-1
!
vtp mode transparent
!
spanning-tree mode rapid-pvst
spanning-tree extend system-id
!
vlan 121
name Faculty/Staff
!
vlan 131
name LEGACY - Kelce OIS
!
vlan 221
name Printers
!
vlan 321
name Labs
!
vlan 421
name Public-Access
!
vlan 521
name Wireless
!
vlan 621
name Dorms-Registered
!
vlan 721
name Dorms-Unregistered
!
vlan 821
name Voice
!
vlan 921
name Management
!
vlan 1021
name Public
!
interface FastEthernet0/1
switchport access vlan 121
switchport mode access
spanning-tree portfast
!
interface FastEthernet0/2
switchport access vlan 131
switchport mode access
spanning-tree portfast
!
interface GigabitEthernet0/1
description *** LINK TO SW-RECCENTER-DIST-1 ***
switchport trunk encapsulation dot1q
switchport mode trunk
switchport nonegotiate
!
interface Vlan1
no ip address
shutdown
!
interface Vlan921
description Management
ip address 10.21.90.20 255.255.254.0
!
ip default-gateway 10.21.90.1
!
Management addressing follows this scheme:
NAME MGMT IP Location
---- ------- --------
sw-building-dist-y 10.21.90.y 1st Floor
sw-building-x-y 10.21.90.xy 1st Floor
sw-building-x-y 10.21.90.xy 2nd Floor
wap-building-x-y 10.21.91.xy 1st Floor W
wap-building-x-y 10.21.91.xy 1st Floor E
wap-building-x-y 10.21.91.xy 1st Floor S
wap-building-x-y 10.21.91.xy 2nd Floor W
wap-building-x-y 10.21.91.xy 2nd Floor E
Management VLAN 921 - 10.21.90.0/23
- Where:
- x = Floor
- y = Unit #
