sh - Source Hashing: assigns jobs to servers through looking up a statically assigned hash table by their source IP addresses.
rr - Robin Robin: distributes jobs equally amongst the available real servers.
※ sh, rr 스캐줄링 weight값을 2로 설정했지만 똑같은 커넥수치가 같음 / weight 옵션 반영안됨
wrr - Weighted Round Robin: assigns jobs to real servers proportionally to there real servers’ weight.
Servers with higher weights receive new jobs first and get more jobs than servers with lower weights.
Servers with equal weights get an equal distribution of new jobs.
