Submit Your Topic Requests for the New CCIE R&S Advanced Technologies Class

As you may know, I will be the lead instructor for our New CCIE R&S Advanced Technologies Class.  The class runs online, and will start Monday April 11th at 07:00 PDT (GMT -7).  If you have an All Access Pass subscription or purchased the live version of the R&S ATC in the past you can attend the live class free of charge by contacting sales. Space is limited so if you want to attend the live version you need to contact sales ASAP.

The class will run least 10 days (not consecutively), but may run as long as 12 – 15 days.  Each class day will run about 8 hours, but may run as long as 10 - 12 hours.  Right now the length of the class is open ended, because there is *so much* content that I’m going to be covering.  I don’t want to rush through topics or skip key topics just to make the class fit into a normal template.  Class length will also it depend on how many questions I get from students during the class.

The purpose of this post is to announce that I am taking student submitted topic requests for the class.  If there is something that you're having trouble understanding during your studies, or have found something that is not covered in enough depth in other classes or products, submit your requests here as a comment, or directly to me via email at [email protected].

I look forward to seeing you in class!

 

 

Brian McGahan, CCIE #8593 (R&S/SP/Security)

[email protected]

Internetwork Expert, Inc.

http://www.INE.com

Toll Free: 877-224-8987 x 705

Outside US: 775-826-4344 x 705

Online Community: http://www.IEOC.com

CCIE Blog: http://blog.INE.com

Comments

  • Brian

    I understand that in a lab environment GRE tunnels can be configured on 3560s, but during the new CoD, can you briefly cover the actual reason that GRE tunnels are not supported by Cisco nor recommended for production networks on the 3560s?  I've read mixed information about it on blogs, et. al.    There was vague info on the Cisco Doc  that mentions a hardware limitation, but  what exactly is the hardware limitation and the mechanics behind it?



    v/r,

    John Gonzalez

  • AFAIK it’s just that GRE isn’t implemented in hardware on that platform, so the forwarding would be really really slow.  For platforms like 6500 with the correct PFC, GRE forwards in hardware.  You can see this in the release notes for that particular version

     

    http://www.cisco.com/en/US/docs/switches/lan/catalyst6500/ios/12.2SX/release/notes/features.html

     

    IP-in-IP tunneling and generic routing encapsulation (GRE) tunneling (hardware-assisted)—The PFC3 and DFC3s support the following tunnel commands:

    http://www.cisco.com/en/US/i/templates/blank.giftunnel destination

    http://www.cisco.com/en/US/i/templates/blank.giftunnel mode gre

    http://www.cisco.com/en/US/i/templates/blank.giftunnel mode ipip

    http://www.cisco.com/en/US/i/templates/blank.giftunnel source

    http://www.cisco.com/en/US/i/templates/blank.giftunnel ttl

    http://www.cisco.com/en/US/i/templates/blank.giftunnel tos

    Other supported types of tunneling run in software on the MSFC3. The PFC3 does not provide hardware acceleration for tunnels configured with the tunnel key command.

    The tunnel ttl command (default 255) sets the TTL of encapsulated packets.

    The tunnel tos command, if present, sets the ToS byte of a packet when it is encapsulated. If the tunnel tos command is not present and QoS is not enabled, the ToS byte of a packet sets the ToS byte of the packet when it is encapsulated. If the tunnel tos command is not present and QoS is enabled, the ToS byte of a packet as modified by PFC QoS sets the ToS byte of the packet when it is encapsulated.

    To configure GRE Tunneling and IP in IP Tunneling, refer to these publications:

    http://www.cisco.com/en/US/docs/ios/12_2/interface/configuration/guide/icflogin.html

    http://www.cisco.com/en/US/docs/ios/12_2/interface/command/reference/irfshoip.html

    To configure the tunnel tos and tunnel ttl commands, refer to this publication:

    http://www.cisco.com/en/US/docs/ios/12_0s/feature/guide/12s_tos.html

    Note the following information about tunnels:

    http://www.cisco.com/en/US/i/templates/blank.gifEach hardware-assisted tunnel must have a unique source address. Hardware-assisted tunnels cannot share a source address even if the destination addresses are different. Use secondary addresses on loopback interfaces or create multiple loopback interfaces. Failure to use unique source addresses may result in control plane failures when software path congestion occurs. (CSCdy72539)

    http://www.cisco.com/en/US/i/templates/blank.gifEach tunnel interface uses one internal VLAN.

    http://www.cisco.com/en/US/i/templates/blank.gifEach tunnel interface uses one additional router MAC address entry per router MAC address.

    http://www.cisco.com/en/US/i/templates/blank.gifThe PFC3A does not support any PFC QoS features on tunnel interfaces.

    http://www.cisco.com/en/US/i/templates/blank.gifThe PFC3B and PFC3BXL support PFC QoS features on tunnel interfaces.

    http://www.cisco.com/en/US/i/templates/blank.gifIn releases earlier than Release 12.2(18)SXE, the PFC3 does not support GRE tunnel encapsulation and de-encapsulation of multicast traffic.

    http://www.cisco.com/en/US/i/templates/blank.gifThe MSFC supports tunnels configured with egress features on the tunnel interface. Examples of egress features are output Cisco IOS ACLs, NAT and PAT (for inside to outside translation), TCP intercept, and encryption.

     

     

    I will talk about this in class though, thanks for the topic suggestion.

     

    Brian McGahan, CCIE #8593 (R&S/SP/Security)

    [email protected]

    Internetwork Expert, Inc.

    http://www.INE.com

    Toll Free: 877-224-8987 x 705

    Outside US: 775-826-4344 x 705

    Online Community: http://www.IEOC.com

    CCIE Blog: http://blog.INE.com

     

    From: ccie-r[email protected] [mailto:[email protected]] On Behalf Of johnpgonz
    Sent: Thursday, March 31, 2011 11:44 AM
    To: Brian McGahan
    Subject: Re: [CCIE R&S] Submit Your Topic Requests for the New CCIE R&S Advanced Technologies Class

     

    Brian

    I understand that in a lab environment GRE tunnels can be configured on 3560s, but during the new CoD, can you briefly cover the actual reason that GRE tunnels are not supported by Cisco nor recommended for production networks on the 3560s?  I've read mixed information about it on blogs, et. al.    There was vague info on the Cisco Doc  that mentions a hardware limitation, but  what exactly is the hardware limitation and the mechanics behind it?

    v/r,

    John Gonzalez




    Internetwork Expert - The Industry Leader in CCIE Preparation
    http://www.internetworkexpert.com

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