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Forum Replies

  1. René,

    Congrats for share this excellent explanation!!! I'm from Brazil and I don't have a good English, but I can understand each word, sentence that you used in this article. I never had understood about this subject, maybe because I really didn't study it with attention and deeply. I'm a beginner Network Admin and when I saw this article in my feed I started to read it and understand it and I'm amazing how you can teach it like this way.

    But I have a doubt where I can't see in examples above. Using this topology, if tomorrow for any reason Blue and Red make a partnership and decide them share your resource between hosted at Blue1 and Red2. How could ISP route the traffic between them?Maybe this article contain the answer, but I can see it.

    Again, Thanks for share your knowledge, keep it and go ahead!!!

    P.S: Sorry for my English mistakes, but I'm not a native English speaker.


  2. Thanks Rene, im now studying EVN, and you mention that

    "When we use VRF lite we have to configure sub-interfaces for each VRF on the Gigabit3 interfaces of ISP1 and ISP2. Each sub-interface belongs to a different VRF and uses 802.1Q encapsulation to differentiate the different VRFs."

    but there's no scenario here in VRF lite where you configure 2 ISP and have a subinterface both on each.

  3. Thanks Rene, great tutorial.

    Let us know when you do a tutorial for MP-BGP, that is of particular interest to me as we will become responsible for a network using MP-BGP in the near future.



  4. Hi Azm,

    Routing context for VRFs only applies to EXEC commands like ping or telnet. It is a bit confusing since it still shows up when you enter config mode:

    R1#routing-context vrf RED
    R1%RED#conf t

    Technically, I could use an EXEC command from the config mode though:

    R1%RED(config)#do ping
    Type escape sequence to abort.
    Sending 5, 100-byte ICMP Echos to, timeout is 2 seconds:
    Success rate is 100 percent (5/5), round-trip min/avg/max = 6/6/7 ms

    Which sends a ping from VRF RED. Just keep in mind it only works for EXEC commands.

  5. Hi Rene,

    In single Router Scenario that you showed your tutorial , Is possible to exchange prefix/Communication from one VRF to other VRF Like Red to Blur or vice versa . Thx


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