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Darrin_20019's avatar
Darrin_20019
Icon for Nimbostratus rankNimbostratus
Jul 20, 2016

LTM unicast to multicast

Does F5 offer a solution for the following?

 

I would like traffic coming into a VIP to be multicast to all the members in a pool

 

4 Replies

  • Well, you wouldn't multicast it to all members. You'd have the member be a multicast address and have the intended targets join that group.

     

    You need to run 12.0 or better for it to work, though.

     

  • Danny_Epperson_'s avatar
    Danny_Epperson_
    Historic F5 Account

    In ...THIS LINKED CONTENT HAS BEEN DELETED... The Bhattman says this wouldn't work as the LTM is not considered a Multicast Router.

     

  • zeiss_63263's avatar
    zeiss_63263
    Historic F5 Account

    Actually PIM support has been added in 12.x versions. But it's not what you need here.

     

    Darrin this might be possible if the pool members were not directly connected to the BIG-IP (EG: a switch is in path). But you can't use a multicast IP address:

     

    (tmos) create net arp 224.1.1.1 ip-address 224.1.1.1 mac-address 01:00:5e:1:1:1 01020063:3: IP Address 224.1.1.1 is invalid, Class D/E addresses not allowed for SelfIP, Static Arp or SNAT.

     

    But you can use a multicast MAC mapped to unicast IP, so as long as the downstream switch plays along it might work:

     

    (tmos) create net arp 10.10.10.10 ip-address 10.10.10.10 mac-address 01:00:5e:1:1:1

     

    I have to assume in this solution that you have one IP that reaches all pool members. You have one pool member "10.10.10.10". Test this, It's just an idea!

     

    Your other alternative is to statically assign a phoney MAC address that forces downstream switches to flood to the VLAN and only put the pool members in that VLAN (for security).

     

    None of this will work if the VLAN is bit directly connected to the BIG-IP. The BIG-IP can only control the MAC address destination on the local link.