Using SoftPro Select with F5 load balancer

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toddsou
Posts: 52
Joined: Wed Jul 25, 2012 9:39 am

Using SoftPro Select with F5 load balancer

Post by toddsou » Fri May 11, 2018 1:30 pm

Hi-

It is my understanding that the SPS Client requires any load balancer which sits between the client and an SPS server farm to allow for session stickiness/affinity.

Our F5 vendor is suggesting that we use their cookie feature to do this. That is, new sessions are issued new cookies, and thus traffic can be appropriately routed based on the presence of the returned cookie in subsequent requests.

So my question is: The SPS client uses the http protocol to communicate to the SPS servers, but will it respect the load balancer's request that an issued session cookie be stored on the client and returned with all further traffic coming from that SPS session ?

Thank you.

-Todd

John Morris
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Location: Raleigh, NC, USA
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Re: Using SoftPro Select with F5 load balancer

Post by John Morris » Fri May 11, 2018 2:31 pm

The SPS client will not store the load balancer's cookie. The SPS application sends an url query params hint called "cid". This value is mantained by the SPS app. The load balancer needs to provide stickiness based on this value. The value itself doesn't have meaning, other than to signal that if the load balancer sees the same value twice, it should route the request to an already routed server.

Upon the load balancer seeing the first unique CID value, it should pick a server to route to and remember the answer. If the load balancer doesn't see the CID value for more than 15 mins, it should be safe for the load balancer to drop the cache entry.
John Morris
Sr. Software Architect
SoftPro

toddsou
Posts: 52
Joined: Wed Jul 25, 2012 9:39 am

Re: Using SoftPro Select with F5 load balancer

Post by toddsou » Fri May 11, 2018 3:00 pm

Thanks, John.

And if I restart the SPS client, will it generate a new cid value ?

John Morris
Posts: 411
Joined: Thu Sep 11, 2008 11:35 am
Location: Raleigh, NC, USA
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Re: Using SoftPro Select with F5 load balancer

Post by John Morris » Fri May 11, 2018 3:10 pm

Yes.
John Morris
Sr. Software Architect
SoftPro

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