Tag Archives: ubuntu

MPLS Topology 1.2

Hopefully this will be my final tweak. This time I’ve added base configs to the CPE devices. It just gives them a hostname and ensures there is no timeout. This prevents you from having to keep logging back in.

Image-wise, it’s the same. Click for the larger image:

MPLS Backbone small MPLS Topology 1.2

This is the .net file contents:

#MPLS 1.1 created 23/02/10
#MPLS 1.2 created 24/02/10
#MPLS 2.0 created 29/03/11 - Changed routers to 3725s and moved idlepc to the 3725 box at the top
#www.mellowd.co.uk/ccie
#Feel free to use and change as you see fit. However if you do use please leave my details here at the top

[localhost:7200]

workingdir = /data/dynamips/working

[[3725]]
image = /data/dynamips/IOS_Images/3725/c3725-adventerprisek9-mz.124-15.T14.UNCOMPRESSED.bin
ram = 142
disk0 = 16
disk1 = 0
ghostios = true
sparsemem = true
idlepc = 0x6026be14

###########################
#                         #
# Mpls Topology   1.2     #
#                         #
###########################

[[Router CR1]]
  model = 3725
  console = 2001
  autostart = true
  #slot3 = NM-1FE-TX
  slot1 = NM-4T
  slot2 = NM-1FE-TX
  s1/0 = AR1 s1/0
  s1/2 = AR3 s1/2
  Fa0/0 = CR3 Fa0/0
  Fa2/0 = CR2 Fa2/0
  cnfg = /data/dynamips/Topology/mpls/CR1.cfg

[[Router CR2]]
  model = 3725
  console = 2002
  autostart = true
  #slot3 = NM-1FE-TX
  slot1 = NM-4T
  slot2 = NM-1FE-TX
  s1/0 = AR2 s1/0
  s1/2 = AR1 s1/2
  Fa0/0 = CR4 Fa0/0
  cnfg = /data/dynamips/Topology/mpls/CR2.cfg

[[Router CR3]]
  model = 3725
  console = 2003
  autostart = true
  #slot3 = NM-1FE-TX
  slot1 = NM-4T
  slot2 = NM-1FE-TX
  Fa2/0 = CR4 Fa2/0
  s1/0 = AR3 s1/0
  s1/1 = GR1 s1/1
  s1/2 = AR4 s1/2
  cnfg = /data/dynamips/Topology/mpls/CR3.cfg

[[Router CR4]]
  model = 3725
  console = 2004
  autostart = true
  #slot3 = NM-1FE-TX
  slot1 = NM-4T
  slot2 = NM-1FE-TX
  s1/0 = AR4 s1/0

[[Router AR1]]
  model = 3725
  console = 2005
  autostart = true
  #slot3 = NM-1FE-TX
  slot1 = NM-4T
  slot2 = NM-1FE-TX
  Fa0/0 = CPE1 Fa0/0
  Fa2/0 = CPE2 Fa0/0
  #cnfg = /data/dynamips/Topology/mpls/AR1.cfg

[[Router AR2]]
  model = 3725
  console = 2006
  autostart = true
  #slot3 = NM-1FE-TX
  slot1 = NM-4T
  slot2 = NM-1FE-TX
  Fa0/0 = CPE4 Fa0/0
  Fa2/0 = CPE3 Fa0/0
  #cnfg = /data/dynamips/Topology/mpls/AR2.cfg

[[Router AR3]]
  model = 3725
  console = 2007
  autostart = true
  #slot3 = NM-1FE-TX
  slot1 = NM-4T
  slot2 = NM-1FE-TX
  Fa0/0 = CPE5 Fa0/0
  Fa2/0 = CPE6 Fa0/0
  #cnfg = /data/dynamips/Topology/mpls/AR3.cfg

[[Router AR4]]
  model = 3725
  console = 2008
  autostart = true
  #slot3 = NM-1FE-TX
  slot1 = NM-4T
  slot2 = NM-1FE-TX
  Fa0/0 = CPE8 Fa0/0
  Fa2/0 = CPE7 Fa0/0
  #cnfg = /data/dynamips/Topology/mpls/AR4.cfg

[[Router CPE1]]
  model = 3725
  console = 2009
  autostart = false
  #slot3 = NM-1FE-TX
  #cnfg = /data/dynamips/Topology/mpls/CPE1.cfg

[[Router CPE2]]
  model = 3725
  console = 2010
  autostart = false
  #slot3 = NM-1FE-TX
  #cnfg = /data/dynamips/Topology/mpls/CPE2.cfg

[[Router CPE3]]
  model = 3725
  console = 2011
  autostart = false
  #slot3 = NM-1FE-TX
  #cnfg = /data/dynamips/Topology/mpls/CPE3.cfg

[[Router CPE4]]
  model = 3725
  console = 2012
  autostart = false
  #slot3 = NM-1FE-TX
  #cnfg = /data/dynamips/Topology/mpls/CPE4.cfg

[[Router CPE5]]
  model = 3725
  console = 2013
  autostart = false
  #slot3 = NM-1FE-TX
  #cnfg = /data/dynamips/Topology/mpls/CPE5.cfg

[[Router CPE6]]
  model = 3725
  console = 2014
  autostart = false
  #slot3 = NM-1FE-TX
  #cnfg = /data/dynamips/Topology/mpls/CPE6.cfg

[[Router CPE7]]
  model = 3725
  console = 2021
  autostart = false
  #slot3 = NM-1FE-TX
  #cnfg = /data/dynamips/Topology/mpls/CPE7.cfg

[[Router CPE8]]
  model = 3725
  console = 2022
  autostart = false
  #slot3 = NM-1FE-TX
  #cnfg = /data/dynamips/Topology/mpls/CPE8.cfg

[[Router GR1]]
   model = 3725
   console = 2023
   autostart = true
   #slot3 = NM-1FE-TX
   slot1 = NM-4T
   Fa0/0 = ISP2 Fa0/0
   #cnfg = /data/dynamips/Topology/mpls/GR1.cfg

[[Router ISP2]]
   model = 3725
   console = 2024
   autostart = false
   #slot3 = NM-1FE-TX
   #cnfg = /data/dynamips/Topology/mpls/ISP2.cfg

And here are the updated config files: http://mellowd.co.uk/ccie/wp-content/uploads/2010/02/mpls.tar2.gz

BGP Lab 12

Topology used is over here: http://mellowd.co.uk/ccie/?p=243

BGP Lab 12:

  • AS7, AS9 and AS11 are all customers of ISP1
  • AS7 has it’s own address space – 77.48.16.0/24 advertised via a loopback
  • ISP1 owns the address space 180.16.0.0/16
  • AS9 has been assigned 180.16.9.0/24 from ISP1 – insert via loopback
  • AS11 has been assigned 180.16.11.0/24 from ISP1 – insert via loopback
  • Ensure that AS7′s address space is advertised to AS9 and AS11
  • ISP1 needs to advertise the entire 180.16.0.0/16 range and not the more specific routes. Ensure AS7 sees only 180.16.0.0/16 HOWEVER it must still know that some routes have come from AS9 and AS11
  • On AS9, configure an attribute so that ISP1 does not advertise the more specific 180.16.9.0/24 address to anyone.
  • You should notice that ISP1 is now not advertising the aggregate because it has inherited the no-export community from above
  • Now on ISP1, ensure that the community is changed so that the aggregate can be advertised again

Click on the thumbnail for the full size topology:

BGP 12 150x150 BGP Lab 12

BGP Lab 11

Topology used is over here: http://mellowd.co.uk/ccie/?p=243

BGP Lab 11:

  • All routers are peered via BGP
  • Router9 has the network 24.83.176.1/24 attached via a loopback
  • Router2 has the network 24.83.177.1/24 attached via a loopback
  • All networks MUST be inserted into the BGP process
  • Now ensure that Router8 and Router1 see the full aggregate of 24.83.176/23 advertised. More specific routes MUST be supressed. i.e. Router1 and Router8 should have the aggregate ONLY – Do this WITHOUT removing any of the networks from the BGP process
  • Now change the configuration so that Router1 and Router8 get the aggregate as well as the more specific routes, however using a community tag (on Router2), ensure that Router1 does NOT advertise the more specific routes to Router6.
  • Router6 should still get the aggregate route
  • Check to make sure Router1 has all the routes and Router6 ONLY has the aggregate route

Click on the thumbnail for the full topology:

BGP 11 150x150 BGP Lab 11

BGP Lab 10

Topology used is over here: http://mellowd.co.uk/ccie/?p=243

BGP Lab 10:

  • CompanyA is a customer of ISP1
  • CompanyA is peered with CompanyB which is NOT a customer of ISP1
  • ISP1 advertises the loopbacks of both Router8 and Router9, however wants to ensure that only it’s own customers know about 8.8.8.8
  • ISP1 does not care that all routers know about 9.9.9.9
  • ISP1 does not trust CustomerA to put the right measure in place, so you need to do it from the ISP1 side.
  • In other words, make sure that CompanyA knows about 8.8.8.8 but force it not to advertise that route any further

Click on the thumbnail for the full topology:

BGP 10 150x150 BGP Lab 10


BGP Lab 9

Topology used is over here: http://mellowd.co.uk/ccie/?p=243

BGP Lab 9:

  • ISP1 is running OSPF internally so that all loopbacks are accessible
  • Router1 has the network 172.20.1.0/24 attached to it (via a loopback)
  • Router8 has the network 172.20.8.0/24 attached to it (via a loopback)
  • Ensure both these networks are advertised by both Router1 and Router8
  • ISP1 contains the entire 172.20.0.0/16 network. Ensure this aggregate is always advertised out, no matter the condition of the more granular networks
  • Using MED, ensure traffic from Router10 to 172.20.1.0/24 goes via Router2 and traffic to 172.20.8.0/24 goes via Router9
  • Ensure the MED comes from the OSPF metric itself

Click on the thumbnail for the full topology:

BGP 9 150x150 BGP Lab 9