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Praveenkumar_18's avatar
Praveenkumar_18
Icon for Nimbostratus rankNimbostratus
Jun 22, 2018

In HA , FOR confic sync and failover option what is the recommended ip ( floting self ip or self ip or dedicated ha vlan IP)?.

In HA , FOR confic sync and failover option what is the recommended ip ( floting self ip or self ip or dedicated ha vlan IP)?.

 

In my environment we are using external self ip but coming to vlan leval we are assigned tarffic group 1 to the floting self ips.

 

Here which ip is taking traffic to next device. As we know traffic group contains flotable iteams.

 

In this case why we assigned external self ip to confirm sync and failover instead of floting self ip?

 

application delivery
LTM

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  • youssef1's avatar
    youssef1
    Icon for Cumulonimbus rankCumulonimbus
    Jun 22, 2018

    Hi,

    First of you can't use floting IP for HA. You can use only self IP.

    what I advise is to create a dedicated vlan for the HA part. if you also want to do mirroring you must have a dedicated vlan, it is F5 which advocates:

    "Configure a dedicated VLAN and dedicated interfaces to process mirroring traffic."

    https://support.f5.com/csp/article/K14135

    but if you do not have a dedicated VLAN and you have no choice. you have the possibility to use an existing vlan.

    So tu sum up if you want to set up HA, you have to:

    • use self IP only.
    • You can use a dedicated vlan (recommended). And if you use a dedicated vlan you do not need to create the floating IP. It is not used in the sync / failover process.
    • Configure a dedicated VLAN and dedicated interfaces to process mirroring traffic (recommende by F5).

    why we assigned external self ip to confirm sync and failover instead of floting self ip?

    Floating IP is used for traffic and not for HA. And in all case when you set up HA you can noticed that you can't choice Floatin IP in device settings for HA builting.

    INFO about Floating IP:

    A floating IP address is used to support failover in a high-availability cluster. The cluster is configured such that only the active member of the cluster "owns" or responds to that IP address at any given time. Should the active member fail, then "ownership" of the floating IP address would be transferred to a standby member to promote it as the new active member. Specifically, the member to be promoted issues a gratuitous ARP, announcing the new MAC address–to–IP address association.

    A virtual IP address refers to the IP address of a virtual server, and is a more nebulous term. With F5 load balancers, for example, the virtual servers are the services (websites, etc.) you want to host.

    More concretely, suppose you have a pair of load balancers in an active-standby cluster. For each interface or VLAN, the load balancers would each have a self IP address, as well as a floating IP address that is shared between both members. When the load balancer relays incoming requests to the back-end nodes, it uses the floating IP address as the source address, so if the load balancer dies, its partner will be able to take over and receive the response. Each website or other service being hosted on the load balancers would have its own IP address, which you could call a "virtual" IP address. (You could say that these virtual IPs "float" as well, since control of them would transfer to the standby node in the event of a failover.)

    Let me know if you need more details.

    regards