Array APV負(fù)載均衡培訓(xùn)

1、2021-11-1APV Technical TrainingConfidential: Array Internal Use Only2021-11-12內(nèi)容內(nèi)容 Array Appvelocity（簡稱（簡稱APV）產(chǎn)品介紹）產(chǎn)品介紹 APV負(fù)載均衡器工作原理負(fù)載均衡器工作原理 APV初始化安裝與基本配置初始化安裝與基本配置 集群配置集群配置 典型組網(wǎng)典型組網(wǎng)Confidential: Array Internal Use Only2021-11-13Array Appvelocity（簡稱（簡稱APV）產(chǎn)品介紹）產(chǎn)品介紹APV 1200 4*1000M ports 1000 Mbps t

2、hroughput Intel Celeron Processor 1GB RAM Confidential: Array Internal Use Only2021-11-14Array Appvelocity（簡稱（簡稱APV）產(chǎn)品介紹）產(chǎn)品介紹APV 2200 4*1000M ports 2*1000M SFP 1500 Mbps throughput Intel P4 Processor 2GB RAM Confidential: Array Internal Use Only2021-11-15Array Appvelocity（簡稱（簡稱APV）產(chǎn)品介紹）產(chǎn)品介紹APV 3200

3、8*1000M ports 2*1000M SFP 2Gbps throughput Intel P4 Processor 4GB RAM Confidential: Array Internal Use Only2021-11-16Array Appvelocity（簡稱（簡稱APV）產(chǎn)品介紹）產(chǎn)品介紹APV 5200 8*1000M ports 4*1000M SFP 8Gbps throughput AMD Quad-Core Processor 4GB RAM Confidential: Array Internal Use Only2021-11-17Array Appvelocit

4、y（簡稱（簡稱APV）產(chǎn)品介紹）產(chǎn)品介紹APV 6200 8*1000M ports 4*1000M SFP 2*10G ports(可選) 10Gbps throughput AMD Quad-Core Processor 8GB RAM Confidential: Array Internal Use Only2021-11-18Array Appvelocity（簡稱（簡稱APV）產(chǎn)品介紹）產(chǎn)品介紹APV 6250 8*1000M ports 4*1000M SFP 2*10G ports12Gbps throughput AMD Quad-Core Processor 8GB RAM

5、Confidential: Array Internal Use Only2021-11-19內(nèi)容內(nèi)容 Array Appvelocity（簡稱（簡稱APV）產(chǎn)品介紹）產(chǎn)品介紹 APV負(fù)載均衡器工作原理負(fù)載均衡器工作原理 APV初始化安裝與基本配置初始化安裝與基本配置 集群配置集群配置 典型組網(wǎng)典型組網(wǎng)Confidential: Array Internal Use Only2021-11-110SLB Terminology Real Service (“Real”)- Represents a physical service which will handle client reques

6、ts Real Service Group (“Group”)- Represents a group of real services which traffic will be distributed to- Defines which load balancing algorithm to use Virtual Service (“Virtual”)- Represents a virtual service that clients can connect to Policy- Associates real service groups with virtual servicess

7、ervice 1service 5service 4service 3service 2Real 1Real 3Real 4Real 5Real 2Group 1Group 2Virtual 1Virtual 2InternetConfidential: Array Internal Use Only2021-11-111Server Load Balancing Example Basic Server Load balancingInternetService GroupReal servicesVirtual IP012345User enters in their

8、browser. Hostname sent to DNS for resolution.1DNS resolves to the Virtual IP address (VIP) of 0.2Client sends request to VIP.3Array proxies request to selected real service.4Further requests from the client may be sent to the same or a different real service, depending on persistency confi

9、guration.5DNSConfidential: Array Internal Use Only2021-11-112SLB Modes Server Load Balancing can be performed in three modes:- Reverse Proxy ModeArray APV proxies all client connections to real services.- Transparent ModeArray APV transparently proxies all client connections to real services.- Trian

10、gle ModeArray APV transparently proxies all client connections to real services.Confidential: Array Internal Use Only2021-11-113Reverse Proxy Mode Packet Flow-Client connects to VIP on Array APV and sends request to Array APV.-Array APV opens a new connection to real service and sends request to ser

11、vice.-service responds to Array APV.1.Array APV responds to Client.VirtualInternetservice1service2Inside InterfaceOutside Interface1234Confidential: Array Internal Use Only2021-11-114Reverse Proxy Mode TranslationsVirtualInternetservice1service2Inside InterfaceOutside Interface1234StepSource IPSourc

12、e PortDestination IPDestination Port1Client-IPClient-PortVirtual-IPVirtual-Port2Inside-IPInside-PortReal-IPReal-Port3Real-IPReal-PortInside-IPInside-Port4Virtual-IPVirtual-PortClient-IPClient-PortConfidential: Array Internal Use Only2021-11-115Transparent Mode Packet Flow-Client sends request to VIP

13、 on Array APV.-Array APV forwards request to real service, maintaining the clients IP.-Real service returns response via client IP (handled by Array APV).1.Array APV forwards response to Client.Virtual IPInternetservice1service2235461Confidential: Array Internal Use Only2021-11-116Transparent Mode T

14、ranslationsVirtual IPInternetservice1service2235461StepSource IPSource PortDestination IPDestination Port1Client-IPClient-PortVirtual-IPVirtual-Port23Client-IPClient-PortReal-IPReal-Port4Real-IPReal-PortClient-IPClient-Port56Virtual-IPVirtual-PortClient-IPClient-PortConfidential: Array Internal Use

15、Only2021-11-117Triangle Transmission ModeTriangle Transmission Arrays Triangle Transmission is specially designed for low-inbound/high-outbound applications such as Video On Demand (VOD), and to accommodate requests in the quickest and most efficient manner. A new system mode “triangle mode” is adde

16、d for this new feature.For triangle transmission, when selecting a proper real server from a group, administrators can use Round Robin (rr), Persistent IP (pi), Hash IP (hi), Consistent Hash IP (chi), Least connections (lc and SNMP (snmp) group method.Confidential: Array Internal Use Only2021-11-118

17、Working Flow Client sends a request to a Virtual IP 0 on Array APV by the router.Array APV forwards the request to a real service. The Virtual IP 0 has been configured as the loopback interface on the real service, so that the request can be received by the real service.The real se

18、rvice returns response to the router directly. Since the default route IP on the real service is set to be , the response will be sent to the router directly The request will pass through APV , the response will be sent from the real server to the client directly without hitting APV .Notes:

19、 triangle transmission SLB health is based on the system IP addresses of the real servers, not the loopback IP addresses. This means when health check is up, the real service might not be available. Triangle Transmission ModeConfidential: Array Internal Use Only2021-11-119負(fù)載均衡算法負(fù)載均衡算法非保持性算法非保持性算法 1,

20、 Round Robin(RR) 2, Least Connection(LC) 3, Fastest Response Time(FRT)保持性算法保持性算法 1, Persistent IP(PI) 2, Hash IP(HI) 3, Consistent Hash IP(CHI) 4, Hash Header(HH) 5, Persistent Hostname(PH) 6, Persistent URL(PU) 7,SSL Session ID(SSLID) 8, Persistent Cookie(PC) 9, Rewirte Cookie(RC) 10, Insert Cookie

21、(IC) 11,Hash Cookie(HC) 12,Embed Cookie(EC) 13,Confidential: Array Internal Use Only2021-11-120Round Robin (rr) Distributes new connections sequentially between available real services.- Example: Connections are distributed to the real services in the following order:1, 2, 3, 4, 5, 1, 2, 3 The “gran

22、ularity” option may be configured so that each real service handles a specific number of new connections before the next service is selected.- Example: Granularity value of “3” illustrates the distribution:1, 1, 1, 2, 2, 2, 3, 3, 3, etc.InternetConfidential: Array Internal Use Only2021-11-121Round R

23、obinClientsRouterAPVServersClient requests are distributed evenly12345678InternetRound Robin (rr)Confidential: Array Internal Use Only2021-11-122Least Connections (lc) Distributes new connections to the real service that has the least number of current connections.- Example: real service 5 has the f

24、ewest current connections, so the next connection will go to real service 5. The “granularity” option can be used to treat real services within the same connection count range as the same; a new real service will not be chosen until this range is exceeded for the current one.InternetConfidential: Ar

25、ray Internal Use Only2021-11-123ClientsRouterServers12InternetDistributes new connections to the real service that has the least number of current connections.462460455465Current ConnectionsLeast Connections (lc)Confidential: Array Internal Use Only2021-11-124Real Service Weighting (rr, lc) Weightin

26、g allows you to change the distribution between real services in the group.- Example: You may set one service to handle twice as many connections as another service. Use weighting if you have a mix of backend services with different performance capabilities. - Example: If you add new services that h

27、ave faster CPUs, you could weight them higher so they receive more connections.Server 1Weight 3Server 5Weight 1Server 4Weight 1Server 3Weight 2Server 2Weight 3Real 1Real 3Real 4Real 5Real 2Group 1Connection 2Connection 3Connection 4Connection 5Connection 1VIP 1Public IPPolicy 1Method Round RobinInte

28、rnetIncomingTraffic from theInternetConnection 6Connection 7Connection 8Connection 11Connection 10Connection 9Connection 12Connection 13Connection 14InternetConfidential: Array Internal Use Only2021-11-125ClientsRouterServersAdministrator sets ratio for distributing Client requests 3:1:1:11456710111

29、2Internet2389Real Service Weighting (rr, lc)APVXConfidential: Array Internal Use Only2021-11-126ClientsRouterServers12Internet10ms5ms20ms17msCurrent Response TimesFastest Response time (frt)Distributes new connections to the real service that has the shortest response time.Confidential: Array Intern

30、al Use Only2021-11-127the same IP request should be assigned to the same server. 123123Persistent IP (pi)Confidential: Array Internal Use Only2021-11-128Hash IP (hi) Distributes new connections to a real service based on a hash of the source IP address.- Client sends a request to the virtual service

31、.- Array hashes source IP address of request to select a real service.- Array forwards all requests with same hash value to the same real service. Note- If a real service fails, persistence will not be maintained for existing clients on healthy services.- Consistent mappings of client IP to real ser

32、vice across multiple Arrays during failover is not guaranteed.Confidential: Array Internal Use Only2021-11-129Consistent Hash IP (chi) Distributes new connections to a real service based on a hash of the source IP address.- Client sends a request to the virtual service.- Array hashes source IP addre

33、ss of request to select a real service.- Array forwards all requests with same hash value to the same real service. Note- If a real service fails, persistence will be maintained for existing clients on healthy services.- Mappings of client IP to real service are consistent across all Arrays so that

34、clients will continue to go to the same real service on failover.Confidential: Array Internal Use Only2021-11-130Hash Header (hh) Distributes new connections to a real service based on a hash of a non-standard/standard HTTP Header - Non-standard header = headers not defined in RFC 2616 (HTTP/1.1) Ex

35、ample:- X-MSISDN header generated by WAP gatewaysAll wireless clients (mobile phones) proxied through a WAP gateway have the same source IP address.Problem for client-IP persistence methods!Options include cookie-persistence and Hash Header methods.WAP gateway can receive MSISDN (phone number) of us

36、er from Radius and insert it into proxied HTTP request as X-MSISDN header.Hash Header on this header provides good load distribution across the real services while maintaining client persistence.Confidential: Array Internal Use Only2021-11-131Persistent Hostname (ph) Distributes new connections to a

37、 real service based on a hash of the hostname found in the HTTP requests Host header sent from the client.- Client sends a request to the virtual service with a Host: header.- Array examines Host: header value to select a real service.- Array forwards all requests with same Host: header value to the

38、 same real service.Confidential: Array Internal Use Only2021-11-132Persistent URL (pu) Distributes new connections to a real service based on a static match of a URL Tag and Value.- Client sends a request to the virtual service with a Tag and Value included in the URL.- Array hashes Value to select

39、a real service.- Array forwards all requests with same Tag and Value to the same real service.Confidential: Array Internal Use Only2021-11-133SSL Session ID (sslsid) SSL Session ID (negotiated during SSL connection setup) is used to maintain a client-to-service binding.- Client opens an HTTPS connec

40、tion to the virtual service.- Array selects a real service and forwards request to it.- Response from real service contains an SSL Session ID.- Array tracks SSL SID and real service combination.- Next request from client contains SSL SID.- Array examines SSL SID and sends request to the same real se

41、rvice that was chosen earlier. May only be used when load balancing SSL connections.Confidential: Array Internal Use Only2021-11-134Persistent Cookie (pc) Real service is selected based on a static match of the cookie name/value pair. - Client sends a request to the virtual service.- Array selects a

42、 real service and forwards request to it.- Response from real service contains a specific cookie with a value denoting that service.- Client receives cookie in response.- Next request from client includes cookie.- Array examines cookie and sends request to proper real service. Each real service with

43、in a group must be configured with a unique cookie value.Confidential: Array Internal Use Only2021-11-135ClientServerHTTP request (no cookie)TCP handshakeTCP handshakeHTTP request (no cookie)HTTP reply (with special cookie)HTTP reply (with special cookie)pickserver HTTP request (with same cookie)TCP

44、 handshakeTCP handshakeHTTP request (with same cookie)HTTP reply (with special cookie)HTTP reply (with special cookie)cookiespecifiesserver First HitSecond HitAPVPersistent Cookie (pc)Confidential: Array Internal Use Only2021-11-136Rewrite Cookie (rc) Array rewrites (modifies) a named cookies value

45、in the service response.- Client sends a request to the virtual service.- Array selects a real service and forwards request to it.- Response from real service contains a specific cookie with a generic value.- Array rewrites cookie value based on the real service.- Client receives cookie in response.

46、- Next request from client includes cookie.- Array examines cookie and sends request to indicated real service. Used to simplify cookie based persistence configuration. All backend services within a group must set the same name=value pair.Confidential: Array Internal Use Only2021-11-137ClientServerH

47、TTP request (no cookie)TCP handshakeTCP handshakeHTTP request (no cookie)HTTP reply (with simple cookie)HTTP reply (with rewritten cookie)pickserver HTTP request (with same cookie)TCP handshakeTCP handshakeHTTP request (with same cookie)HTTP reply (with simple cookie)HTTP reply (with updated cookie)

48、cookiespecifiesserver First HitSecond HitAPVRewrite Cookie (rc)Confidential: Array Internal Use Only2021-11-138Insert Cookie (ic) Array automatically inserts a Cookie in the service response- Client sends a request to the virtual service.- Array selects a real service and forwards request to it.- Re

49、sponse from real service does not contain a cookie, but cookie persistence is needed.- Array creates a cookie based on the real service and inserts it in the response.- Client receives cookie in response.- Next request from client includes cookie.- Array examines cookie, strips out cookie, and sends

50、 request to same real service as first request. Used in cases where the web site does not have built-in cookie support.Confidential: Array Internal Use Only2021-11-139ClientServerHTTP request (no cookie)TCP handshakeTCP handshakeHTTP request (no cookie)HTTP reply (no cookie)HTTP reply (with inserted

51、 cookie)pickserver HTTP request (with same cookie)TCP handshakeTCP handshakeHTTP request (no cookie)HTTP reply (no cookie)HTTP reply (updated cookie)cookiespecifiesserver First HitSecond HitAPVInsert Cookie (ic)Confidential: Array Internal Use Only2021-11-140Hash Cookie (hc) Real service selection i

52、s based on a hash of the specified cookies value. Used when each client browser session to the web site results in a unique cookie value for that browser session.Confidential: Array Internal Use Only2021-11-141ClientServerHTTP request (no cookie)TCP handshakeTCP handshakeHTTP request (no cookie)HTTP

53、 reply (with cookie)HTTP reply (with cookie)pickserver HTTP request (with same cookie)TCP handshakeTCP handshakeHTTP request (with same cookie)HTTP reply (with cookie)HTTP reply (with cookie)cookie hash specifiesserver First HitSecond HitThird HitServerTCP handshakeHTTP request (with same cookie)HTT

54、P reply (with cookie)cookie hash specifiesserver TCP handshakeHTTP request (with same cookie)HTTP reply (with cookie)APVHash Cookie (hc)Confidential: Array Internal Use Only2021-11-142Embed Cookie（ec） Embed cookie allows us to embed a section of a cookie value to the cookie can be sent back to the s

55、ame server. - Client sends a request to the virtual service.- Array selects a real service and forwards request to it.- Response from real service contains a cookie.- Array embeds a specific value based on the real service.- Client receives cookie in response.- Next request from client includes cook

56、ie.- Array examines cookie and removes the embedded value, then sends request to indicated real service. Unlike rewrite cookie, we will strip out the modifications that the ArrayOS has made in the request. so the backend will see the original cookie.Confidential: Array Internal Use Only2021-11-143Em

57、bed Cookie（ec）ClientServerHTTP request (no cookie)TCP handshakeTCP handshakeHTTP request (no cookie)HTTP reply (with cookie)HTTP reply (with embedded cookie)pickserver HTTP request (with same cookie)TCP handshakeTCP handshakeHTTP request (with original cookie)HTTP reply (with cookie)HTTP reply (with

58、 embedded cookie)cookiespecifiesserver First HitSecond HitAPVConfidential: Array Internal Use Only2021-11-144幾種算法的區(qū)別幾種算法的區(qū)別SideHitCookie MethodMethodicrcecpcHc服務(wù)器端服務(wù)器端First HitNo CookieOrigin Server CookieOriginServerCookieOrigin ServerOrigin ServerSecond HitWritten Cookie客戶端客戶端Array Insert CookieAr

59、ray Written CookieArrayEmbedCookieOrigin ServerOrigin ServerInsert CookieInsert Cookie ：Array會(huì)自動(dòng)插入一個(gè)Cookie。Re-Write CookieRe-Write Cookie：Array在Response時(shí)重寫Cookie的值，服務(wù)器看到的已經(jīng)是修改后的Cookie。Embed CookieEmbed Cookie：Array在Response時(shí)在服務(wù)器回應(yīng)的Cookie里，插入一段值。Persistent CookiePersistent Cookie：根據(jù)服務(wù)器的Cookie的值進(jìn)行保持（靜態(tài)匹配）Hash CookieHash Cookie：根據(jù)服務(wù)器的Cookie的值進(jìn)行保持（不需要靜態(tài)匹配，Hash Cookie的值）Confidential: Array Internal Use Only2021-11-145SLB Virtual Services The following parameters are associated with a virtual service:- Virtual service protocol (udp, tcp, ftp, http; tcps and https for SSL)- Virtual service name- Vir