Load balancer (VPX) Manual

Load balancer (VPX) Manual

Table of Contents 1. Outline... 3 1.1 Purpose... 3 1.2 Scope... 3 1.3 Driving system of ucloud server Load balancer... 4 2. Method of subscription/request for Load balancer... 5 2.1 Product subscription... 5 2.2 How to request products... 6 2.3 How to terminate products... 8 2.4 How to change product options... 9 3. Description of Load balancer... 10 3.1 Options for Load balancer (LOAD BALANCING ALGORITHMS)... 10 3.2 Characteristics of ucloud server Load balancer... 11 3.3 TCP OFFLOAD.... 12

1. Outline This document describes how to use Load balancer, a supplementary service of olleh ucloud. 1.1 Purpose This document aims to explain methods of requesting the service on portal, detailed executing and setting the service in regard to using Load balancer service of ucloud server. 1.2 Scope This document describes how load on VM can be dispersed in ucloud environment by a using supplementary service, the Load balancer. This document s scope of use is as follows. Method of requesting/terminating and creating/deleting Load balancer Setting method for Load balancer

1.3 Driving system of ucloud server Load balancer Load Balancing is a technology for dispersing client requests to multiple servers (customer VM) to optimize utilization of resources. Limited number of servers can cause overload to provide numerous clients with service and their performance can be degraded. Upon request, ucloud server Load balancer conveys each client s request to a server which is the most capable of processing the request and blocks bottleneck state by using load dispersion technology. As shown in figure, a client goes through VIP, IP of VPX VM, to make access to service. VPX VM is dispersed to Customer Account IP/port(PUBLIC IP/PORT) through established method of Load Balancing options. Requests dispersed to each port reach each service and respond to client s requests through port forwarding and virtual router of NAT function.

2. Method of subscription/request for Load balancer This describes how to subscribe and request Load balancer service. 2.1 Product subscription Make access to https://ucloudbiz.olleh.com/en-us/ and select Service Highlight Supplementary service Load balancer subscribe Product. Check whether the service normally added (completion of subscription) and so is Load balancer on product subscription information.

2.2 How to request products Click Cloud console in the top right on portal. Click order Now Supplementary Service Load balancer Services available. Click next after entering/checking each request details in request items Check duplication after entering name of Load balancer Select Stipulation/Non-stipulation and bandwidth Select options for Load balancer (see 3-x)

Enter Load balancer port Enter redirection URL in case of exceeding bandwidth Select server for Load balancer, It is automatically registered on the list with additional click after entering public/private port. (So is Port forwarding.) Check request details and complete the request. You can see the completed request as the screen below.

2.3 How to terminate products Supplementary service Load balancer Select the relevant Load balancer and click

Delete. 2.4 How to change product options Change. Supplementary service Load balancer Select the relevant Load balancer and click

You can change items as below. (except name of Load balancer, stipulation, bandwidth and Load balancer port) - Options for Load balancer, URL of guide page in exceeding bandwidth, Add/Delete Load balancer target server 3. Description of Load balancer 3.1 Options for Load balancer (LOAD BALANCING ALGORITHMS) Round robin

Method of Round robin performs load balancing by circulating a client s requests in order. Example of Round robin option Least Connection Least Connection performs load balancing by selecting a connection of the least number of Active connections between VPX (LB) and servers (VM1, VM2, VM3) to execute a client s requests. Example of Least Connection option Hashing(Source IP Hash, Source IP Hash + Port) Hash method performs load balancing based on information on client s Source IP and Source IP + Port by results of hash. Hash method is mainly used to make requests of the same information subject to load balancing by one server. 3.2 Characteristics of ucloud server Load balancer Technologies of Basic Load balancer

Technologies of basic L4 Load balancer exactly perform TCP Session to each server but Load balancer on data requested by actual users is not executed. Technologies of ucloud Load balancer Technologies of ucloud Load balancer enables exact Load balancer requested by actual users with load balancing on each data that users request with all servers. Comparison of Basic and ucloud Load balancer Basic Load balancer ucloud Load balancer Performance Small-sized Middle and large-sized Action configuration Influence on existing service Selecting options for Load balancer Selecting network bandwidth Checking Source IP of Client Load balancer performed by an established Virtual Router High Available (3 options choosable) Unavailable Unavailable Assigning dedicated VM for Load balancer by customers Low Available (4 options choosable) Available (100/300/500Mbps choosable) Available (only on HTTP service) Price Free of charge Charged (flat rate by bandwidth) Stability Low High (duplex configuration) 3.3 TCP OFFLOAD TCP Offload using TCP Multiplexing

1 3-way handshake is progressed by responding to client s TCP request from VPX in place of server. 2 Client transmits a request on application. 3 VPX creates server and TCP Connection. 4 Client s request on application is conveyed to server. 5 Upon client s additional requests, this is reused when TCP Connection between VPX and server is idle. 6 Client s multiple requests are processed through Connection between Server and VPX. Advantages of using TCP Multiplexing - Optimizing client s all requests by making correlation between Transport Layer and application request(layer7) independent - Phenomenal reduction of CPU usage in server by offloading Transport Layer Processing from server or cache

Server setting for TCP Offload (for users of Aparche2.0 web server) - Set as KeepAlive On in /etc/httpd/conf/httpd.conf. - Apply changes by demon re-drive. - Change setting values for improving performance of Aparche2.0 web server. (recommended) Server setting for TCP Offload (for users of IIS 7.0 web server) 1 Start Management tool IIS manager Local PC POP Down Site folder Default Web Site 2 Http response header (in the top right) General header setting Check HTTP maintenance of connection and apply