Just a quick post on filtering outbound OSPF advertisements. I had some struggle with this config today.

config router prefix-list
  edit “filter-outbound”
  config rule
    edit 1
      set prefix 10.10.0.0 255.255.0.0
      unset ge
      unset le
    next
    edit 2
      set prefix 10.20.0.0 255.255.0.0
      unset ge
      unset le
    next
    edit 3
      set action deny
      set prefix any
      unset ge
      unset le
    next
  end
 next
end
!
config router ospf
 set router-id 1.1.1.10
  config area
    edit 1.1.1.1
      config filter-list
        edit 1
          set list “filter-outbound”
          set direction out
        next
end

Like a said: a quick-and-dirty  note

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René Jorissen

Co-owner and Solution Architect at QMonkeys

René Jorissen works as Solution Architect for QMonkeys in the Netherlands. Network Infrastructures are the primary focus. René works with equipment of multiple vendors, like HPE Networks, FortiNet, SentinelOne, Phished, Holm Security, Microsoft services and many more. René is Aruba Certified Edge Expert (ACEX #26), Aruba Certified Mobility Expert (ACMX #438), Aruba Certified ClearPass Expert (ACCX #725), Aruba Certified Design Expert (ACDX #760), CCNP R&S, FCNSP and Certified Ethical Hacker (CEF) certified. You can follow René on Twitter and LinkedIn.

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