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Bastien_8356's avatar
Bastien_8356
Icon for Nimbostratus rankNimbostratus
Apr 11, 2011

How to configure HA active/active ?

I have servers located in 2 different data centers, same architecture.

 

Web servers are sending request to an LB where there are MySQL server behind it.

 

 

I want to configure those LB to be in Active/Active mode so they are splitting the traffic between them, and if 1 fails, the other take both loads.

 

 

Right now LB in location A only take traffic from Web server at location A. Same for B.

 

 

So my new architecture would be that both LB will share the load from A and B.

 

 

 

So far, I configured both Big-IP with the self IP and the same floating IP. I'd like to know if this configuration will be enough, do I have to configure the Network Failover ?

 

If yes, how do I configure it ? The management address will have to be the same as the management port ?

 

 

Thanks for your help !

 

 

4 Replies

  • Hamish's avatar
    Hamish
    Icon for Cirrocumulus rankCirrocumulus
    Ahh...

     

     

    If I'm reading your post correct, then that's not how Active/Active works...

     

     

    Active/Active denotes the fact that both units can serve virtual servers simultaneously... Not both serving the same VS and IP address at the same time... To configure it, simply place into active/active config (A checkbox under the HA options) and then assign individual VS's to either unit 1 or unit 2. The VS will then 'live' on the unit specified. If one of the units goes down, the other uni will takeover BOTH units load.

     

     

    So you'd have 2x VS's. One for MySQL A, one for MySQL B. MySQL A VS would be on unit 1, MySQL B VS would be on unit 2. Then simply configure web A to use MySQL A VS and web B to use MySQL B VS.

     

     

    H
  • Oh ok, so I shouldn't use the floating address at all ? Can I use the self IP as the VS address ?

     

    I don't need the failover network ?

     

     

    Let's say LB A has the VS address .1 and the B has .2, if LB A fails, how the WEB A will know to use the VS B ?
  • Hamish's avatar
    Hamish
    Icon for Cirrocumulus rankCirrocumulus
    When an LTM takes over a unit, it takes over all the VS's for that unit. When an LTM takes over a VS, it responds for the IP address associated with it.

     

     

    This assumes you have a network spanned over the two DC's of course... WHich I'm assuming is correct...

     

     

    H
  • OK. The 2 LB are on the same sub-network. I want WEB A to point to VS A on LB A, and WEB B to point to VS B on LB B.

     

    If one fails, all WEB will go to VS A + B on the active LB.

     

     

    I configure both Virtual Server on LB A and sync. But how WEB A will know to go to LB A or B ? Since both LB has the 2 VS...

     

     

     

    Also, I configured the fail over network, they are both showing Active. When I unplugged one of them, the other show : common.status.ACTIVE (1 and 2).

     

    It's not telling me that the other unit is off, neither in the logs, just tells me "Unit 1 and 2"

     

     

    What should I do ?