Again, sorry for not explaining my intentions too well.
I have Origin1 and Origin2 in my Cloudflare’s LB pool. Users from around the world are getting connected either to Origin1 to Origin2, without much predictibility.
In my cloud service, Origin1 and Origin2 are actually stateful (in-memory state + algorithms). This means that for certain resources ALL USERS who want to access a specific resource, they need to connect to a single origin which is controlling that resource.
My original idea was somehow manipulating Cloudflare’s cookies to force all users of a specific resource to a specific origin which is controlling that resource.
My current idea is simply having a unique hostname per each origin and directing the users there through an explicit connect through a non-LBed hostname, without messing up with CF’s load balancer (as you pointed out the cookies are not intended to be used directly)
Hope it makes sense.