文档介绍：F5 GTM 解决方案介绍
Traffic Management Basics
Within the
Data Center
To the
Data Center
ISP A
ISP B
Data Center to
Data Center
异地容灾中常见的应用与网络恢复技术
按预案手工实现站点接管(Tier3/4)
手动修改客户端访问目的地址(缺点:切换慢、维护工作量大)
手动修改DNS解析记录方式(缺点:错误设置DNS启示录的后故是相当严重的)
通过事先写好的脚本实现自动的热接管(Tier5)
应用层重定向(缺点:时间长、扩展性差)
通过广域网流量管理方案提供永不停顿的系统运行能力(Tier6)
Getting Users to the Best Available Data Center
Router
L-DNS
BIG-IP GTM
BIG-IP LTM
Corporate Servers
Site 1 (Primary)
Client
Router
BIG-IP LTM
Corporate Servers
Site 2 (Back up)
BIG-IP GTM
主要功能与特性:应用智能、可管理性与高性能
感知应用,及时发现灾难
自动切换,通知用户改变数据访问点
F5 BIG-IP GTM (Global Traffic Manager)
支持流量在数据中心的动态负载均衡
解决关联应用在多数据中心的协同问题
灵活的规则定义--iRules
支持IPV6应用
图形界面的DNS管理工具
TMOS
全球领先的广域网流量管理方案
异地容灾自动恢复的最佳选择
BIG-IP GTM将故障切换的时间缩短到几十秒钟!!!
User wants to browse
get_host_by_name() called by browser, which causes DNS query to Local DNS (LDNS)
Local DNS recurses:
Ask Root for , get back NS record for .com
Ask .com for , get back NS record for .
Ask for , get back A record
Return A record to puter
User’puter
Stores A record in memory
get_host_by_name() returns the address of browser
Browser opens connection to address:80 and does a GET /
Web page response
标准DNS解析流程
Public
Root DNS Server
(one of 16 from )
Web Server in Timbuktu
.com DNS Server
DNS Server
Local DNS
A Record for ?
Go ask .com
A Record for ?
Go ask
A Record for ?
A Record for ?
Tip: GTM operates here, as an intelligent DNS, monitoring multiple redundant resources and distributing traffic to them
GTM
WIP .com
Pool
User wants to browse
Users PC queries to Local DNS (LDNS)
Local DNS recurses:
Ask Root for ,
Ask .com for
Ask for
AME record Root for .com
Ask .com for .com
Ask GTM for .com
GTM receives DNS query on its Listener
Checks to see if .com matches a Wide IP definition
Checks for persistence records
Checks the Wide IP pool for the most available virtual server
Returns the IP a