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Joe_Francis's avatar
Joe_Francis
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Feb 09, 2015

Load balancing issues - Windows web servers

Hello All

 

I am having load balancing issue with Windows web servers

 

Server - Windows 2000 Application - Web server TCP Port - 80 Load balancing - Round robin Persistence - cookie

 

LTM ver - 10.2.1 Final

 

What i see is - Serv 1 - 75Active connection Sevr 2 - less than 4

 

Please can i get some direction and advices?

 

10 Replies

  • This can happen because of 2 reasons:

     

    1. You are using cookie persistence, so it is possible that 1 client or a group of clients have opened most of the connections.

       

    2. On the pool you are using round-robin load balancing algorithm. It may happen that 1 pool member gets all the long-standing connections and the other gets only the short-lived ones. This will cause pool member 1 to accumulate connections which might skew the balance over time. If this is the case, use "least connections" load-balancing algorithm.

       

    Best

     

  • If you can change the persistence to something other than cookie and a method (w/ CARP), you can use least sessions LB algo. As Amit had mentioned, if not, try least connections member/node.

     

  • Sorry my bad - We dont use Cookie persistence , instead we use a 4hr Source address persistence.

     

    • NikhilB's avatar
      NikhilB
      Icon for Employee rankEmployee
      Have you tried least sessions in that case?
  • if i remember correct , i think we tried least connection with cookie persistence , I am requesting business to approve and perform a test using least connection and 4hr source address persist

     

    • NikhilB's avatar
      NikhilB
      Icon for Employee rankEmployee
      least connection doesn't work with cookie persistence.
    • NikhilB's avatar
      NikhilB
      Icon for Employee rankEmployee
      least connection doesn't work with cookie persistence.
    • shaggy's avatar
      shaggy
      Icon for Nimbostratus rankNimbostratus
      note: least connections works with cookie persistence - it will still send new connections to the pool member with the fewest active TCP connections. least sessions won't work with cookie persistence as cookie persistence does not use the persistence table (https://support.f5.com/kb/en-us/solutions/public/12000/100/sol12105.html)
  • ohh oaky least connection and 4hr source address persist - will this be fine or is there any better recommendation

     

    • mikeshimkus_111's avatar
      mikeshimkus_111
      Historic F5 Account
      Are your clients coming through a NAT device before hitting the BIG-IP? If they are, then BIG-IP cannot see the true client IP and you will get connection clumping if you are using source persistence. Cookie persistence should work fine with least connections load balancing (this is the default in our HTTP-based iApps), so I recommend giving that a try.