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zaphod42_101190's avatar
zaphod42_101190
Icon for Nimbostratus rankNimbostratus
May 15, 2008

GTM & LTM implementation troubles

Hi, new to the forums here and hope to get some assistance on problem I’m facing with load balancing on the GTM. Got the LTM up and running a few months back with no issues but due to my lack of familiarity with GTM (or anyone else in the team) seem to be stuck on the current implementation.

 

 

First, an overview (refer to diagram attached also..)

 

 

1)Main DNS server outside delegate’s traffic to the GTM for www.bookstore.com via wip.bookstore.com on the GTM. DNS delegation works fine for this.

 

2)GTM has 2 Vlans , external on DMZ switch segment (192.168.1.3 self) and internal connected to the LTM (10.10.10.26).

 

3)No issues with connection to LTM via bigip_add and able to retrieve Virtual servers automatically.

 

4)While there are 2 ISP’s no link balancing being done on customer side as traffic of apps on DMZ switch either choose ISP A or B. For the GTM, I added in the internal IP of the 2 FW_ISP as my default_gw pool and set it to my default_route.

 

5)NAT is being done on the FW_ISP’s.

 

6)LTM (with web accelerator) load balances the web servers with Virtual server ip 10.10.10.11. No issues with LTM or WebAcc as this has been configured and running 3 months back.

 

7)Previous load balancing for public ip’s was done via the main DNS server thru an A record ( bookstore.com IN A 100.100.100.10 & 200.200.200.20).

 

 

 

The current issue I’m facing is , how do I load balance the public IP’s on the GTM if both the GTM and LTM are private IP segments. Is this setup even possible ?

 

 

An easy way out would be to just tag the public NAT ip’s (100.100.100.10 & 200.200.200.20) to the WIP but wouldn’t that kind of defeats the purpose of having LTM & GTM connected together no ?

 

 

Also do note, that only one pool member is seen as up if I do the above as we can’t ping the public ip when going out via the same isp link (100.100.100.10 can’t be pinged when default_gw pool selects FW_ISP A).

 

 

Anyone done something similar?

 

 

Apologies if I sound totally noobish but GTM’s are totally alien to me. Installed Link controllers before and had no issues as we were directly controlling the links.

 

 

Feel free to ask if you do not understand what I’ve posted.

 

 

Thanks

 

config
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2 Replies

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  • JRahm's avatar
    JRahm
    Icon for Admin rankAdmin
    May 15, 2008
    Just thinking through what I think you are trying to accomplish:

     

     

    create two virtual servers: Global Traffic->Servers->LTM->Virtual Servers->Add

     

     

    name ISP1, address 100.100.100.10, translation 10.10.10.11

     

    name ISP2, address 200.200.200.20, translation 10.10.10.11

     

     

    Create pool with both virtual servers, create wip with the pool.

     

     

    Obviously this needs to be tested, but if GTM complains or doesn't work due to mapping to the same LTM vip, you could always create a duplicate vip on the LTM for the server pool.
  • zaphod42_101190's avatar
    zaphod42_101190
    Icon for Nimbostratus rankNimbostratus
    May 16, 2008
    Thanks a lot for the replies.

     

     

    Before this , i did the reverse of what citizen_elah posted , with 10.10.10.11 & translation as 100.100.100.10 or 200.200.200.20 and it didn't work though. Will try that again. Personally we have recommended to the customer to have the GTM on a public ip segment but they insisted on having it on the DMZ. Nothing much to be done there i guess.