Virtual Server Connetion Limit vs Pool member connection Limit

Question

Hello,&nbsp;
We are evaluating setting connection limits for a load balanced application, and I want to be sure about the differences between setting the limit at the virtual server level and setting it for each pool member. As I had already read in AskF5 and DevCentral, I see that for the pool member option I'll be able to configure the Override option for persistence and configure TCP request queuing, which, on the other hand, may be a concern when used along with Oneconnect.
So, is there any recommendation for using one of the options or other important considerations?&nbsp;
We are running LTM v11.4.1 HF7&nbsp;
Thanks.&nbsp;

hannes_rapp · Answer

Hi Zoe, I'll throw in some ideas that I would consider myself.&nbsp;
If you want to limit incoming clientside connections, apply a connection limit on each of the Pool Members. A limit on a Virtual Server is not that good since there will be no true load-balancing if persistency is used. Some nodes will always have more connections than others.&nbsp;
&nbsp;Use the override option if needed but in this case you should slightly lower the Connection Limit you set per Pool Member (-15% or -20%). i.e If your Pool Member can sustain 1k connections, reduce the Connection Limit to 850 or less if you use the override option.&nbsp;&nbsp;The TCP request queue is something you may consider as the last resort. If by any means possible, see if you can add more pool members to suppress the need of creating a queue. If you want to proceed by creating a TCP request queue, I'd recommend setting a Queue Limit not higher than 25% of the Connection Limit of a single pool member.

hannes_rapp_162 · Answer

Hi Zoe, I'll throw in some ideas that I would consider myself.&nbsp;
If you want to limit incoming clientside connections, apply a connection limit on each of the Pool Members. A limit on a Virtual Server is not that good since there will be no true load-balancing if persistency is used. Some nodes will always have more connections than others.&nbsp;
&nbsp;Use the override option if needed but in this case you should slightly lower the Connection Limit you set per Pool Member (-15% or -20%). i.e If your Pool Member can sustain 1k connections, reduce the Connection Limit to 850 or less if you use the override option.&nbsp;&nbsp;The TCP request queue is something you may consider as the last resort. If by any means possible, see if you can add more pool members to suppress the need of creating a queue. If you want to proceed by creating a TCP request queue, I'd recommend setting a Queue Limit not higher than 25% of the Connection Limit of a single pool member.

helena_101649 · Answer

Thank very much, Hannes. I'll keep that in mind.&nbsp;

wasfi_182818 · Answer

What's the cli command to set the TCP connection limit for a pool member please?&nbsp;
Kindly
Wasfi&nbsp;

wasfi_182818 · Answer

What's the cli command to set the TCP connection limit for a pool member please?&nbsp;
Kindly
Wasfi&nbsp;

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Virtual Server Connetion Limit vs Pool member connection Limit

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