F5负载均的衡关键技术.ppt

负载均衡关键技术 负载均衡算法 服务器健康检查 会话保持技术 HTTP流量压缩 连接优化技术 带宽管理 BIG-IP 工作原理 BIG-IP 负载均衡算法 Round Robin(轮巡) Ratio(比率) Priority(优先权) Least Connections(最小连接数) Fastest(最快响应速度) Observed(观察模式) Predictive(预测模式) 智能算法 UIE + Irules Round Robin Ratio Fastest Fastest – some time later Least Least – some time later Observed Predictive Minimum Active Members Minimum Active Members Fallback Host 服务器负载均衡关键技术 负载均衡算法 服务器健康检查 会话保持技术 HTTP流量压缩 连接优化技术 带宽管理 服务器健康检查 BIG-IP 服务器健康检查 ICMP TCP Service ECV (Extend Content Verify) EAV (Extend Application Verify) External 主机检查 Steps Packets sent to IP Addresses If no response, then no traffic sent to associated Nodes Example - ICMP 服务检查 Steps Opens TCP connection (IP Address : service) Connection closed If TCP connection fails, then no traffic sent to associated Nodes Example – TCP 内容检查 交互的应用检查 健康检查模版 External Service Check #!/bin/sh # these arguments supplied automatically for all external pingers: # $1 = IP (nnn.nnn.nnn.nnn notation or hostname) # $2 = port (decimal, host byte order) # $3 and higher = additional arguments # # In this sample script, $3 is the regular expression # pidfile=/var/run/pinger.$1..$2.pid if [ -f $pidfile ] then kill -9 `cat $pidfile` /dev/null 21 fi echo $$ $pidfile node_ip=`echo $1 | sed s/::ffff://` #echo GET / | /usr/bin/nc $node_ip $2 2 /dev/null | grep -E -i $3 /dev/null /usr/bin/curl -m 3 http://$node_ip:$2$3 2 /dev/null | grep $4 /dev/null status=$? if [ $status -eq 0 ] then echo up fi rm -f $pidfile 服务器负载均衡关键技术 负载均衡算法 服务器健康检查 会话保持技术 HTTP流量压缩 连接优化技术 带宽管理 Persistence Concepts BIG-IP 会话保持(Session Persistence) Simple Persistence Destination Persistence SSL Persistence Cookie Persistence (Insert, Rewrite, Passive Hash) MSRDP Persistence SIP Persistence Universal Persistence Simple Persistence Based on Source IP Address Assumes no change in IP Address Netmask Address Range Treated as Single Source SSL Persistence Based on SSL Session ID Remains Constant When Client IP Address Changes Persistence Lost if Bro