wrr 101

1998 by Dr. Zhangwensong, this project is one of the earliest free software projects in China. LVS is mainly used for multi-server load balancing for the network layer. In a server cluster system built by LVS, the load balancing layer of the front end is called the director server, and the server group layer that serves the backend is called real server. Get an overview of the LVS infrastructure.LVS has three modes of operation, namely Dr (direct Routing), TUN (tunneling IP Tunneling), NAT (net

because all request packages and reply packets require the Director Server to parse and regenerate, affecting efficiency. At the same time, LVS load balancer has 10 scheduling algorithms, namely RR, WRR, LC, WLC, LBLC, LBLCR, dh, sh, sed, NQFor detailed LVS instructions, see PortalIn this paper, we will use LVS to realize MySQL read-write load balancing, keepalived Avoid single point of failure of nodes.Lvs+keepalived Configuring the Environment prep

, Regardless of the actual load condition and connection status on the server.? Weighted round call scheduling: WRR (Weighted Round Robin) The "Weighted round call" scheduling algorithm dispatches access requests based on the different processing capabilities of real server. You can set different scheduling weights for each real server, and for a relatively good real server, you can set a higher weight, and for a less powerful real server, you can set

:1500 metric:1Interrupt:9 Base address:0xc000[Root@lvs-gs001 ipvsadm-1.24]# IpvsadmIP Virtual Server version 1.2.1 (size=4096)Prot Localaddress:port Scheduler Flags-> remoteaddress:port Forward Weight activeconn inactconn[root@lvs-gs001 ipvsadm-1.24]# Ipvsadm--help[root@lvs-gs001 ipvsadm-1.24]# ipvsadm--set 5 #--set TCP tcpfin UDP set connection timeout values[root@lvs-gs001 ipvsadm-1.24]# ipvsadm-a-t 172.28.95.245:80-s wrr-p add virtual service with

Scheduler Flags -> remoteaddress:port nbsp forward Weight activeconn inactconn TCP 10.1.1.166:www RR -> 10.1.1.164:www nbs P route 1 nbsp 483 -> 10.1 .1.163:www route 1 483 N bsp; IP VirTual Server version 1.2.1 (size=4096) prot localaddress:port Scheduler Flags -> remoteaddress:port forward Weight activeconn inactconn TCP 10.1.1.166:WWW R R -> 10.1.1.164:www route 1 0 5 -> 10.1.1.163:www nbsp ; route 1 0 nbs

Architecture diagramThe installation steps are omitted.158.140 keepalived.conf! Configuration File for keepalivedglobal_defs {#全局标识模块 Notification_email {#定义邮件通知 [emailprotected] #目标邮箱} notification_email_from [emailprotected] #发送邮箱 Smtp_ser ver 127.0.0.1 #发送邮箱的smtp服务器 smtp_connect_timeout #smtp服务器连接超时时间 router_id lvs_2}vrrp_instance vi_1 { State BACKUP #本实例启动状态: Master/backup interface eth0 #监控的网络接口 Virtual_rou ter_id #vrrp实例 (same as a group master standby server Settings) Priority #优先级

; RemoteAddress:Port Forward Weight ActiveConn InActConnTCP 192.168.150.173:3306 wrr persistent 60-> 192.168.150.171:3306 Local 3 0 0TCP 192.168.150.174:3306 wrr persistent 60-> 192.168.150.172:3306 Route 3 0 0-> 192.168.150.171:3306 Local 1 0 0 Status of B after A fault Prot LocalAddress:Port Scheduler Flags-> RemoteAddress:Port Forward Weight ActiveConn InActConnTCP 192.168.150.173:3306

: 192.168.150.173 (write)R-VIP: 192.168.150.174 (responsible for reading)Client: any. You only need to access the above three IP addresses.3.2 architecture DiagramThe architecture diagram is as follows:3.3 design principles (Exceptions)1. server A and server B use binlog to synchronize data through the mysql slave process.2. enable two virtual IP addresses through keepalived: W-VIP/R-VIP, one responsible for writing, one responsible for reading, to achieve read/write separation.3. When both A an

the same time) You can also modify the source IP address (cip --> dip) and target IP address (vip --> rip) of the Request Message for forwarding; Note: The first three types are standard, and the fourth type is post-added. The kernel may not be supported by default, and you need to compile the kernel automatically. (1) VIP is a public IP address; RIP and DIP are private IP addresses, which may not be in the same IP network, but must communicate with each other through routes; (2) The source IP

. -----Load Balancer ConfigurationConfiguring the alias Card Ifconfig eth0:1 192.168.1.181 netmask 255.255.255.0 up # ④ manually perform configuration add LVS server and increase two RS Ipvsadm-cIpvsadm--set 30 5 60Ipvsadm-a-T 192.168.1.181:80-s wrr-p 20Ipvsadm-a-T 192.168.1.181:80-r 192.168.1.178:80-g-W 1Ipvsadm-a-T 192.168.1.181:80-r 192.168.1.179:80-g-W 1 [Delete method]

situation of each server, dynamically select a real server to respond to user requests, then the dynamic selection is how to implement, in fact, we are here to say the load scheduling algorithm, according to different network service requirements and server configuration, Ipvs implements the following eight kinds of load scheduling algorithms, here we detail the most commonly used four scheduling algorithms, the remaining four scheduling algorithms please refer to other information.A)RR Polling

theLetter3, each internal RS node gateway address, must be configured as the scheduler lb private LAN within the physical network card address。。。Omitted####################### #IPVS调度器实现了如下十种负载调度算法: LVs scheduling algorithm10 Kinds of scheduling algorithmsFixed scheduling algorithm: Rr,wrr,dh,shDynamic scheduling algorithm: Wlc,lc,lblc,lblcr,sed,nq.Three most commonly used RR WRR WLC10 scheduling algorithm

192.168.200.1 smtp_connect_timeout 30 router_id LVS_DEVEL}vrrp_instance VI_1 { state MASTER interface eth0 virtual_router_id 51 priority 100 advert_int 1 authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { 192.168.200.10 }}virtual_server 192.168.200.10 80 { delay_loop 6 lb_algo wrr lb_kind DR net_mask 255.255.255.0 protocol TCP real_server 192.168.200.138 80 {

Kerugaki-Blog Parkhttp://www.cnblogs.com/kailugaji/Software that needs to be prepared:Jdk,eclipse,exe4j,inno Setup CompilerFirst, the Java source program--Personal income tax:Package Math;import Javax.swing.JOptionPane;Kerugaki Http://www.cnblogs.com/kailugaji/public class Wrrtax {public static void main (string args[]) {string Mone Y Enter your income double x, y; Double tax=0; Joptionpane.showmessagedialog (NULL, "personal income tax calculator \ n" + "Producer:" + "Kerugaki \ n" + "http:/

hosts:1. mysql installation (slightly)2. keepalived InstallationYum Install keepalived2. LVS InstallationYum Install IpvsadmFive, configuration1. Configure master-slave replication for MySQL (slightly)2. Configure keepalivedThe configuration on MasterVi/etc/keepalived/keepalived.conf[Plain]View Plaincopy ! Configuration File for Keepalived Global_defs { router_id mysql-ha } Vrrp_instance Vi_1 { State BACKUP Interface eth1 VIRTUAL_ROUTER_ID 90 Priority 100 Advert_int

(0.04 sec) 4, do or match: for searching one of two strings, use | as follows: [sql]mysql>select Roleid from V9_admin_ Role where Roleid REGEXP ' 1|3 '; +--------+ |roleid | +--------+ | 1 | | 3 | +--------+ 2 Rowsin Set (0.00 sec) 5, matches one of several characters: matches any single character. As follows: [sql]mysql>select name from V9_collection_node , where name REGEXP ' 005-[123 ]‘; +-----------------+ |name | +-----------------+ |101