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Numb3r_4_102532's avatar
Numb3r_4_102532
Icon for Nimbostratus rankNimbostratus
Nov 26, 2015

F5 GTM Topology - load balance one wideip with 2 datacenters

Hi DC members,

 

I have some confusions in deploying the GTM toplogy. As from my understanding, there are 2 methods to LB using the topology : 1. WideIP Level 2. Pool Level

 

Here is the setup :

 

DC 1 :

 

2 x LTM (HA) , 1 x GTM

 

DC 2 :

 

2 x LTM (HA) , 1 x GTM

 

2 sets of users : Country A, Country B.

 

The requirements :

 

Both users (CountryA & CountryB) will be using the same WideIP (ie:

 

Scenario:

 

User from Country A will have to connect apps in DC1 , and in the event of server failure in DC1, it will be routed to DC2, User from Country B will have to connect apps in DC2 , and in the event of server failure in DC2, it will be routed to DC1, vice versa.

 

Below is my configurations :

 

Wide IP : www.abc.com , PoolA : VS1 in DC1, VS2 in DC2, LB Method : Topology

 

Topology records:

 

Subnet A , Destination DC1, Weight = 200 | Subnet A , Destination DC2, Weight = 100 | Subnet B , Destination DC2, Weight = 200 | Subnet B , Destination DC1, Weight = 100

 

Does this configurations correct?

 

Thanks in advance!

 

application delivery
BIG-IP DNS
gtm
topology

4 Replies

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  • Brad_Parker's avatar
    Brad_Parker
    Icon for Cirrus rankCirrus
    Nov 27, 2015

    When you say your LB method is Topology, have you assigned that to the WideIP or the pool itself? If you assign it to the WideIP then the WideIP will use the topology records to choose a pool not a VS within the pool. If you assign the method of topology to your pool then the topology records will then be used to choose a VS from within the pool.

     

    • Numb3r_4_102532's avatar
      Numb3r_4_102532
      Icon for Nimbostratus rankNimbostratus
      Nov 28, 2015
      Hi Brad, Yes, the LB method = Topology was assigned to the WideIP. While the pool itself was assigned , LB = Round Robin. I am also curious here about the topology thingy, what about if we have multiple WideIP, with multiples topology, how does the GTM decide which topology to be used for the respective WideIP's? Bcoz from my logic view, all the topology records is like a global attributes and does not associate with the WideIP.
  • Brad_Parker_139's avatar
    Brad_Parker_139
    Icon for Nacreous rankNacreous
    Nov 27, 2015

    When you say your LB method is Topology, have you assigned that to the WideIP or the pool itself? If you assign it to the WideIP then the WideIP will use the topology records to choose a pool not a VS within the pool. If you assign the method of topology to your pool then the topology records will then be used to choose a VS from within the pool.

     

    • Numb3r_4_102532's avatar
      Numb3r_4_102532
      Icon for Nimbostratus rankNimbostratus
      Nov 28, 2015
      Hi Brad, Yes, the LB method = Topology was assigned to the WideIP. While the pool itself was assigned , LB = Round Robin. I am also curious here about the topology thingy, what about if we have multiple WideIP, with multiples topology, how does the GTM decide which topology to be used for the respective WideIP's? Bcoz from my logic view, all the topology records is like a global attributes and does not associate with the WideIP.