I'm not sure why you would want to do that on a 2-core firewall, I assume since it is standalone you want all firewall workers and SND's sharing core 0 while SMS management functions use core 1? Your performance will almost certainly be terrible since there will be so many CoreXL components fighting each other for a single core, what you might want to do instead is disable CoreXL completely from cpconfig which should give you one SND on Core 0 and one Firewall Worker on Core 1. Management processes will take a backseat to kernel operations occurring in the single SND and single Firewall Worker.
If you want to do it anyway, you'll need to configure the fwaffinity.conf file, see R80.30 Performance Tuning Administration Guide. In general though setting up manual affinity is not a desirable path to start down if it can be avoided.
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