User guide 0908
Transcription
User guide 0908
EXCELIANCE – ZAC des Metz 3 Rue du petit robinson – 78350 Jouy en Josas Tél: 01.30.67.60.74 – Fax: 01.75.43.40.70 – email: [email protected] – www.exceliance.fr 1 Technical training Administration ALOHA Load Balancer Application Level Optimization & High Availability High availability & load balancing solution for high performance Web servers & TCP applications © Copyright Exceliance 2007-2009 - - www.exceliance.fr 2 Sommaire This guide is intended to any IT staff who is or will be in charge of setting up, configuring, and maintaining an ALOHA LB system in production. All basic functionnalities will be covered in this guide that will allow any attendee to be able to set up an ALOHA LB in a production environment without help. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 3 Table of contents Sommaire I. II. III. IV. Introduction -------------------------------------------------------------------------------------------------------------------------- 7 a. General facts ----------------------------------------------------------------------------------------------------------------- 7 b. Definition --------------------------------------------------------------------------------------------------------------------- 8 c. Problems ---------------------------------------------------------------------------------------------------------------------- 9 d. Risks & consequences ----------------------------------------------------------------------------------------------------- 10 e. Technical solution ---------------------------------------------------------------------------------------------------------- 11 f. State of the Art ------------------------------------------------------------------------------------------------------------- 12 ALOHA L B characteristics-------------------------------------------------------------------------------------------------------- 13 a. Versions --------------------------------------------------------------------------------------------------------------------- 13 b. ALB 500 overview ---------------------------------------------------------------------------------------------------------- 14 c. ALB 2K overview ----------------------------------------------------------------------------------------------------------- 15 d. ALB 4K – 8K & 16K overview --------------------------------------------------------------------------------------------- 16 e. Specifications --------------------------------------------------------------------------------------------------------------- 17 f. Energy savings ------------------------------------------------------------------------------------------------------------- 18 Implementation cases ------------------------------------------------------------------------------------------------------------- 19 a. In a DMZ ---------------------------------------------------------------------------------------------------------------------19 b. Complementary to an existing L4 load balancer ------------------------------------------------------------------------ 20 c. For intranet applications -------------------------------------------------------------------------------------------------- 21 d. Multi-sites configuration -------------------------------------------------------------------------------------------------- 22 Graphical User Interface ---------------------------------------------------------------------------------------------------------- 23 a. Factory settings ------------------------------------------------------------------------------------------------------------ 23 b. Setup Wizard --------------------------------------------------------------------------------------------------------------- 24 c. Configuration --------------------------------------------------------------------------------------------------------------- 25 d. Services --------------------------------------------------------------------------------------------------------------------- 26 e. Services details ------------------------------------------------------------------------------------------------------------- 27 f. Address translation -------------------------------------------------------------------------------------------------------- 31 © Copyright Exceliance 2007-2009 - - www.exceliance.fr 4 Table of contents Sommaire V. VI. g. IP access list (ACL) -------------------------------------------------------------------------------------------------------- 32 h. Network Flow --------------------------------------------------------------------------------------------------------------- 33 i. TCP load balacing ---------------------------------------------------------------------------------------------------------- 34 j. Transaction securization protocol ---------------------------------------------------------------------------------------- 35 k. Level 7 load balancing ----------------------------------------------------------------------------------------------------- 36 l. Events logs ------------------------------------------------------------------------------------------------------------------ 37 m. Statistics -------------------------------------------------------------------------------------------------------------------- 38 n. Monitoring ------------------------------------------------------------------------------------------------------------------ 39 Quick setup (wizard) --------------------------------------------------------------------------------------------------------------- 40 a. Schema --------------------------------------------------------------------------------------------------------------------- 40 b. Starting the wizard -------------------------------------------------------------------------------------------------------- 41 c. Network interfaces -------------------------------------------------------------------------------------------------------- 42 d. Network interfaces aggregation ----------------------------------------------------------------------------------------- 43 e. IP addressing -------------------------------------------------------------------------------------------------------------- 44 f. IP routing ------------------------------------------------------------------------------------------------------------------ 45 g. VRRP ------------------------------------------------------------------------------------------------------------------------ 46 h. Admin access --------------------------------------------------------------------------------------------------------------- 47 i. Load balancing ------------------------------------------------------------------------------------------------------------- 48 j. Virtual server -------------------------------------------------------------------------------------------------------------- 49 k. Configuration summary --------------------------------------------------------------------------------------------------- 51 l. Configuration generation ------------------------------------------------------------------------------------------------- 52 Level 7 load balancing (HTTP, RDP, HTTPS, FTP) ------------------------------------------------------------------------------- 53 a. Generated Configuration (monitoring) ---------------------------------------------------------------------------------- 53 b. Generated Configuration (LB Layer7) ----------------------------------------------------------------------------------- 54 c. Configuration – global section ------------------------------------------------------------------------------------------- 55 d. Configuration – default settings ----------------------------------------------------------------------------------------- 56 © Copyright Exceliance 2007-2009 - - www.exceliance.fr 5 Table of contents Sommaire e. Configuration – virtual servers ------------------------------------------------------------------------------------------- 57 f. Configuration – real servers farm --------------------------------------------------------------------------------------- 59 g. Adding virtual servers ----------------------------------------------------------------------------------------------------- 65 h. Stopping virtual servers -------------------------------------------------------------------------------------------------- 70 i. Adding real servers -------------------------------------------------------------------------------------------------------- 72 j. Stopping real servers ------------------------------------------------------------------------------------------------------ 74 k. Session persistence -------------------------------------------------------------------------------------------------------- 75 l. Content switching --------------------------------------------------------------------------------------------------------- 78 m. SSL setup ------------------------------------------------------------------------------------------------------------------- 80 VII. Level 4 load balancing (TCP) ------------------------------------------------------------------------------------------------------ 91 a. Network flow --------------------------------------------------------------------------------------------------------------- 92 b. Configuration (LB Layer 4) ----------------------------------------------------------------------------------------------- 95 c. Directors configuration --------------------------------------------------------------------------------------------------- 96 VIII. ALOHA LB High availability ------------------------------------------------------------------------------------------------------ 104 a. VRRP between two Aloha ----------------------------------------------------------------------------------------------- 104 b. Configuration synchronization in cluster mode ----------------------------------------------------------------------- 107 IX. Monitoring ------------------------------------------------------------------------------------------------------------------------- 109 X. Statistics --------------------------------------------------------------------------------------------------------------------------- 111 XI. Events logs ------------------------------------------------------------------------------------------------------------------------ 113 XII. Faq ---------------------------------------------------------------------------------------------------------------------------------- 114 a. Configuration error control ---------------------------------------------------------------------------------------------- 114 b. Configuration backup ---------------------------------------------------------------------------------------------------- 118 © Copyright Exceliance 2007-2009 - - www.exceliance.fr 6 Introduction General facts Sommaire The ALOHA is a solution dedicated to application platforms (Web, filtering relay, directories, CRM, ERP, thin client servers,…) high availaibility and load balancing. Proposed as an appliance, it is partly based on the L7 open source load balancer HA Proxy and L4 LVS (Linux Virtual Server) both known for their liability and performance. These two software are mainly used all over the world in high performance and heavy constraints production environments. The ALOHA includes an enriched and optimised HA Proxy running on top of a dedicated linux embedded operating system. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 7 Introduction Definition Sommaire What is load balancing ? Although one server power is always limited, a Web application should run on many servers to support a constant growth of the number of users. This is what is called application scalability. For intranet applications, scalability management is quite easy because the number of users is already known and will rarely grow suddenly. On the other hand, for Internet portals or e-commerce applications, the regular growth of the number of users as the constant growth of high bandwidth links are both heavy loading factors. In this case, IT managers need to find solutions to achieve scalability by balancing the load amongst many servers, by using internal applications processes or/and by platform architecture reorganization. Load balacing allows to use many servers that will then provide the same services and will all do the same job (although it is possible to dedicate some servers to specific as we will see later). But, increasing the number of servers may also increase the risk of failure in the platform. This risk must be seriously addressed. Ability to guarantee the service availability is calles high availability. This feature is frequently required in a load balacing environment which is the main reason why most of the people are mixing these two concepts together. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 8 Introduction Problems Sommaire Problems Performance Availability Security Application bugs OpEX © Copyright Exceliance 2007-2009 - - www.exceliance.fr 9 Introduction Risks et consequences Sommaire RISKS Low performances Wait states, latency Connection problems Sessions loss Unavailability Information leaks © Copyright Exceliance 2007-2009 - CONSEQUENCES Financial loss recurrent bad performance Load Peaks bad performance Unavailability time X number of impacted users Bad company image Over expenses Business opportunities loss Legal issues - www.exceliance.fr 10 Introduction Technical solution Sommaire Solutions enforce scalability Reduce infrastructure costs Management simplification Application protection © Copyright Exceliance 2007-2009 - - www.exceliance.fr 11 Introduction State of the Art Sommaire Access : May be redundant using BGP protocol. Multisite configuration possible via DNS. Level 3-4 load balancer : Scalable & Highly available infrastructure. Front end Scalability : Web Acceleration & security (costly L7 treatments) : SSL, cache, compression,… SSL – proxy cache Level 7 load balancer: Scalable & highly available application. Persistence, monitoring, troubleshooting, logs, content switching… Applications: Runs on dedicated or shared servers. Heavy applications need more servers © Copyright Exceliance 2007-2009 - - www.exceliance.fr 12 Aloha characteristics Versions Sommaire Aloha LB appliances are proposed in the following form factor : 1U rack appliances with very low power consumption (10 to 57 Watts @ full load), Embedded appliance on SSD (bootable firmware on rack servers of major vendors (IBM, HP, DELL, Supermicro,…), Virtual appliances (VMWARE™ image for ESX/VI). © Copyright Exceliance 2007-2009 - - www.exceliance.fr 13 Aloha Caracteristics ALB 500 Overview Sommaire Front panel : 12 3 4 Rear panel : 5 6 © Copyright Exceliance 2007-2009 - 7 8 9 - www.exceliance.fr 1. CPU activity 2. Flash Activity 3. Network Activity 4. Factory reset 5. Serial port 6. Network Port 7. Network Port 8. Network Port 9. USB Ports 10. Main Power 10 14 Aloha Caracteristics ALB 2K Overview Sommaire 1 2 3 4 Slot 1 10 Front panel : 5 6 7 8 9 Slot 2 Rear panel : Hotplug Power 1 © Copyright Exceliance 2007-2009 - 1. Serial Port 2. Network Port 3. Network Port 4. Network Port 5. Activity LED 6. Serial Port 7. Network Port 8. Network Port 9. Network Port 10. Power plug 11. Power plug 11 Hotplug Power 2 - www.exceliance.fr 15 Aloha Caracteristics ALB 4K – 8K – 16K Overview Sommaire 1 Front panel : 5 6 7 8 91011 12 234 Rear panel : 13 © Copyright Exceliance 2007-2009 - 14 15 - www.exceliance.fr 1. LCD 2. Not used 3. Not used 4. Not used 5. Not used 6. Console port 7. USB Ports 8. Network Port 9. Network Port 10. Network Port 11. Network Port 12. Activity LED 13. Serial Port 14. On/Off switch 15. Power plug 16 Aloha Caracteristics Specifications (french) Sommaire © Copyright Exceliance 2007-2009 - - www.exceliance.fr 17 Aloha Caracteristics Energy savings Sommaire Power Consumption Operational (full load) ALOHA 500 ALOHA 2K ALOHA 4K ALOHA 8K ALOHA 16K 10 W 10-20 W 40 W 53 W 57 W © Copyright Exceliance 2007-2009 - - www.exceliance.fr 18 Implementation cases In a DMZ Sommaire © Copyright Exceliance 2007-2009 - - www.exceliance.fr 19 Implementation cases Complementary to an existing L4 load balancer Sommaire © Copyright Exceliance 2007-2009 - - www.exceliance.fr 20 Implementation cases For Intranet applications Sommaire © Copyright Exceliance 2007-2009 - - www.exceliance.fr 21 Implementation cases Multi-sites configuration Sommaire © Copyright Exceliance 2007-2009 - - www.exceliance.fr 22 GUI Factory settings Sommaire http://192.168.0.200:4444 or http://192.168.1.200:4444 http://192.168.0.200:4444 admin admin © Copyright Exceliance 2007-2009 - - www.exceliance.fr 23 GUI Wizard Sommaire This tab allows to : Launch the step by step configuration wizard. Be careful : Using this wizard, any previous settings will be replaced To avoid any error, stop the wizard before the end and restart the ALOHA. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 24 GUI Configuration (Setup) Sommaire This tab allows to : Identify system (name, version, firmware, id,…), Know licensing state, Import, export, save and reset configuration. Show firmware revision. Install or delete a licence file. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 25 GUI Services Sommaire This tab allows to manage services : View a service state and start mode. Configure a service. Start a service. Stop a service. Restart a service. Reload a service. Apply a configuration. Cancel a configuration. Synchronize a configuration (cluster mode). © Copyright Exceliance 2007-2009 - - www.exceliance.fr 26 GUI Services details Sommaire Provide system configuration: host name, date,... Log management and configuration (export to syslog server) service. Instance for system events management Instance for application events management Instance for trafic events management Instance for console events management © Copyright Exceliance 2007-2009 - - www.exceliance.fr 27 GUI Services details Sommaire Network interfaces and IP configuration management service. Instance dedicated to interface 0 Instance dedicated to interface 1. Instance dedicated to interface 2. IP routing service management Ports redirection & IP translation rules service. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 28 GUI services details Sommaire IP ACL management service Network flow classification management L4 (TCP) load balancing management service L7 load balancing management service in proxy mode ALOHA high availability (cluster mode) CLI secured access management © Copyright Exceliance 2007-2009 - - www.exceliance.fr 29 GUI Services details Sommaire Time synchronization management service (log time stamping) SNMP monitoring management ALOHA configuration synchronization (cluster) SSL management SNMP trap or email notification configuration Web UI access configuration © Copyright Exceliance 2007-2009 - - www.exceliance.fr 30 GUI Address translation (NAT) Sommaire This tab allows to : Manage NAT rules, Push NAT rules to another ALOHA in the cluster (synchronize) © Copyright Exceliance 2007-2009 - - www.exceliance.fr 31 GUI IP Access lists (IP Acl) Sommaire This tab allows to : Manage IP ACLs. Push IP ACLs to another ALOHA in the cluster (synchronize). © Copyright Exceliance 2007-2009 - - www.exceliance.fr 32 Graphical user interface Network Flows Sommaire This tab allows to : Manage flow identification rules which will be used in L4 load balancing configuration. Synchronize this configuration to a peer ALOHA. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 33 GUI L4 load balancing (LB Layer4) Sommaire This tab allows to : Create L4 load balancing configuration. This config may be pushed (synchronized) to a peer ALOHA. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 34 GUI Transaction securization protocol (SSL) Sommaire This tab allows to : Configure SSL settings. Manage SSL certificates. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 35 GUI Level 7 load balancing (LB Layer7) Sommaire This tab allows to : Manage L7 load balancing configuration. Synchronize this config to a peer ALOHA. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 36 GUI Event logs (Logs) Sommaire This tab allows to : © Copyright Exceliance 2007-2009 - - www.exceliance.fr View system events. View application logs. Study trafic logs. Get details on potential misconfiguration errors (console log). 37 GUI Statistics (Stats) Sommaire This tab allows to : Visualize real time stats about detailed load and requests volume for each front end and back ends. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 38 GUI Monitoring Sommaire This tab allows to : View system activity. Get instant details on servers states. Follow real time state of servers. Verify activity level of L4 & L7 load balancing. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 39 Quick setup (Wizard) Schema (example) Sommaire Datacenter ALB-VA 192.168.0.155 Aloha Master WebSRV 192.168.0.201 192.168.0.254 WebSRV2 192.168.0.202 VirtualSRV Users site © Copyright Exceliance 2007-2009 - - www.exceliance.fr 40 Quicl setup (Wizard) Starting the wizard Sommaire This step allows to : Start the wizard. This step only allow to go to next step or to cancel the wizard. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 41 Quick setup (Wizard) Network interfaces Sommaire This step allows to : Configure physical network interfaces. Select interfaces speed (10 / 100 / 1000 Mbit/s). Select negociation mode (half duplex or full duplex). Describe each interface (giving a name). © Copyright Exceliance 2007-2009 - - www.exceliance.fr 42 Quick setup (Wizard) Interfaces aggregation Sommaire This step allows to : Aggregate network interfaces (bonding). © Copyright Exceliance 2007-2009 - - www.exceliance.fr 43 Quick setup (Wizard) IP addresses Sommaire This step allows to : Configure IP adresses for each network interface (admin adresse, internal addresses or public addresses). Be careful : When you use an ALOHA cluster (2 ALOHA in active/passive mode), the shared services IP addresses will be presented by VRRP service and will be configured next step.. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 44 Quick setup (Wizard) IP routing Sommaire This step allows to : Define IP routes to allow the ALOHA to reach other networks. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 45 Quick setup (Wizard) VRRP (Virtual redundant router protocol) Sommaire This step allows to : Ensure service high availability mode between two ALOHA (cluster mode). The VRRP IP address equals to the service address which will be presented by VRRP service. The VRRP ID is a number between 1 and 255 affected to every machine in the cluster (this ID must be unique on your network). Priority number (between 1 to 254) indicates the node’s priority in the cluster (higher priority takes traffic first). © Copyright Exceliance 2007-2009 - - www.exceliance.fr 46 Quick setup (Wizard) Admin access Sommaire This step allows to : Configure admin access mpodes to the ALOHA. The ‘SSH’ section relates to configuration access mode to the CLI. The ‘Web interface’ section allows you to control the access mode to the Web interface. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 47 Quick setup (Wizard) Load balancing Sommaire This step allows to : Configure the load balancing operating mode as well as virtual servers. Activate IP address translation mode (for multiple DMZ use or to keep source client IP address when configured in network cutting mode). Activate port translation (if your servers are using private non routable IP addresses). Activate ACLs (to restrict access to or from some IP asdresses). Create one or many virtual servers (real servers group). © Copyright Exceliance 2007-2009 - - www.exceliance.fr 48 Quick setup (Wizard) Virtual server (1) Sommaire This step allows to : Associate an IP adresses/ports list behind which is hosted a service on a server farm. Manage load balancing parameters for a particular virtual server (LB mode, method, cookie, time outs,…). Add additional server in the virtual server. Configure healthchecks parameters for real servers. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 49 Quick setup (Wizard) Virtual server (2) Sommaire This step allows to : Add new virtual servers. Edit virtual server configuration. Delete virtual servers. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 50 Quick setup (Wizard) Configuration summary Sommaire This step allows to : View configuration synthesis Apply you new configuration © Copyright Exceliance 2007-2009 - - www.exceliance.fr 51 Quick setup (Wizard) Configuration generation Sommaire This step allows to : Save and validate the ALOHA configuration you have made and apply it after a reboot. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 52 Level 7 load balancing Generated configuration (monitoring) Sommaire The wizard helped you to create a new configuration. You may see it in the ‘monitoring’ tab © Copyright Exceliance 2007-2009 - - www.exceliance.fr 53 Level 7 load balancing Generated Configuration (LB Layer7) Sommaire The wizard has generated a new commented configuration which is shown in the ‘LB layer 7’ tab. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 54 Level 7 load balancing Configuration – global section Sommaire This section is used for « HA Proxy » integration global parameters in the ALOHA. Le paramètre « chroot » autorise à changer la racine du processus une fois le programme lancé, de sorte que ni le processus, ni l'un de ses descendants ne puissent remonter de nouveau à la racine. Aussi, il est important d'utiliser un répertoire spécifique au service pour cet usage, et de ne pas mutualiser un même répertoire pour plusieurs services de nature différente. Pour rendre l'isolement plus robuste, il est conseillé d'utiliser un répertoire vide, sans aucun droit, et de changer l'uid du processus de sorte qu'il ne puisse rien faire dans ledit répertoire. Le paramètre « user » permet de spécifier un nom d’utilisateur . Il est possible d’utiliser un identifiant numérique (uid). Le paramètre « group » permet de spécifier un nom de groupe. Il est possible d’utiliser un identifiant numérique (gid). Le paramètre « daemon » permet de mettre le processus en arrière plan. Il s’agit du socket sur laquelle se connectent les différents outils de l’interface (ainsi que le snmp) pour récupérer les compteurs. © Copyright Exceliance 2007-2009 - - www.exceliance.fr Be careful : EXCELIANCE advise you not to modify these parameters as they could greatly impact the ALOHA configuration. 55 Level 7 load balancing Configuration – default settings Sommaire This section is used to define default parameters that will be used in the next configuration sections. « option httpclose » activate/deactivate passive connection closing (a workaround to « keep alive »). « option dontlognull » activate/deactivate logs for connections without requests. « option redispatch » activate/deactivate session redistribution in the case a connection may have failed. « option contstats » activates constant update of traffic statistics. In the case of a connection failure to a server, it is possible to retry several times (either to another server when load balancing is on). The maximum number of retries is defined by « retries » parameter. « timeout « timeout « timeout « timeout « backlog » defines the number of connections with no « ACK » before triggering SYNFLOOD protection process. connect» Defines the maximum wait time for a successful connection to a server. http-request » Defines the maximum wait time to get a full HTTP request. queue » Defines the maximum time to wait before freeing a connection. tarpit » Defines the duration time during which « tarpited » connections will be maintained. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 56 Level 7 load balancing Configuration – virtual servers Sommaire This section is used to define the parameters for the first virtual server (front end). « bind » Defines one or several listen IP adresses:ports for each virtual server. « mode http » If set, defines instance operation mode in a pure HTTP mode. « log global » Activates logs for this instance using global log parameters. « option httplog » Activates detailed HTTP requests logs with session state and detailed counters. « maxconn » defines the maximum number of concurrent connections which will be accepted by this front end. Au-delà de ce nombre, les connexions en excès resteront dans la « backlog » du système. Over limit connections will be kept in the system backlog and treated sequentially. « timeout client » defines the maximum idle time for the client side (in milliseconds) « default_backend » defines the backend to use when no « use_backend » specific rule have been defined. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 57 Level 7 load balancing Schema update Sommaire Datacenter ALB-VA 192.168.0.155 WebSRV4 192.168.0.204 WebSRV 192.168.0.201 WebSRV5 192.168.0.205 Aloha Master WebSRV2 192.168.0.202 192.168.0.254 VirtualSRV2 VirtualSRV Users site © Copyright Exceliance 2007-2009 - - www.exceliance.fr 58 Level 7 load balancing Configuration – real servers farm Sommaire This section relates to real servers (back end) load balancing parameters. « balance » defines which load balancing algorythm will be used in the farm. « roundrobin » will use each real server in a round robin way using server’s weight. A (Weight=1) B (W =1) A (W =1) B (W =1) A (W =2) (W =2) Identical weights © Copyright Exceliance 2007-2009 - A B (W =1) A (W =2) A (W =2) B (W =1) Different weights - www.exceliance.fr 59 Level 7 load balancing Configuration – real servers farm Sommaire This section relates to real servers (back end) load balancing parameters. « leastconn » ALOHA will choose the server which manage the lowest number of connections A (Connections=10) B (C=5) © Copyright Exceliance 2007-2009 - A (New connection) - www.exceliance.fr B n=6) (Connections=10) (Connections=6) 60 Level 7 load balancing Configuration – real servers farm Sommaire This section relates to real servers (back end) load balancing parameters. « balance source » ALOHA will use a source client IP hash to always connect the client on the same real server. PC1 IP=64.3.1.150 PC1 A PC2 PC2 IP=86.30.5.12 B © Copyright Exceliance 2007-2009 - - www.exceliance.fr 61 Level 7 load balancing Configuration – real servers farm Sommaire This section relates to real servers (back end) load balancing parameters. « balance uri » allows to redirect a connection to a real server based on the URI hash divided by the total weight of active servers. http://www.serveur.com/recherche/catalog/?productId=8202b A http://www.serveur.com/recherche/profil/?memberId=0061h B © Copyright Exceliance 2007-2009 - - www.exceliance.fr 62 Level 7 load balancing Configuration – real servers farm Sommaire This section relates to real servers (back end) load balancing parameters. « cookie » allows to activate session persistence using a cookie. « cookie insert » indicates that the cookie will be inserted in the response. (This session cookie will not be stored on the client hard disk). « cookie indirect » defines that the cookie will only be inserted after the server will have been elected by the load balancing. « cookie nocache » recommended option when there is a proxy cache server on the data way between ALOHA and client « option httpchk » use the specified HTTP request to proceed the healthcheck (HEAD for default HTTP header). « option forwardfor » activates the use of the « x-forwarded-for » field in the requests to real servers (useful to keep source IP) « fullconn » Advanced tuning parameter (threshold for dynamic limit) (by default equals to « maxconn » value ). « timeout server » defines the maximum time ALOHA will wait a response from real servers (in millisecond). © Copyright Exceliance 2007-2009 - - www.exceliance.fr 63 Level 7 load balancing Configuration – real servers farm Sommaire This section relates to real servers (back end) load balancing parameters. « server » real server declaration ( server <name> <address>[:port] [param*…]) « name » internal name assigned to this real server (will appear in logs and interface). « address » server’s IPv4 address. « port » server’s TCP port to use. « cookie » defines a session cookie (cookie <name>) « weight » Used to define server’s weight (used by load balancing algorythms). « maxconn » maximum concurrent connections for this server. Exceding connections will be hold in the queue or redirected to other servers. « check » Activates healthchecks. « inter » defines time interval between 2 checks (in milliseconds by default). « fall » defines the required number of failed checks to declare this server as unoperational (failover). « rise » defines the required number of successful checks to declare this server as operational again (failback). © Copyright Exceliance 2007-2009 - - www.exceliance.fr 64 Level 7 load balancing Adding virtual servers Sommaire To add a new front end : Select the two configuration sections (frontend & backend) from an existing virtual server. Cut & paste your selection Make your modifications (IP, names, parameters,…). © Copyright Exceliance 2007-2009 - - www.exceliance.fr 65 Level 7 load balancing Adding virtual servers Sommaire Validate your configuration by clicking on the « OK » button. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 66 Level 7 load balancing Adding virtual servers Apply this configuration by clicking on the « apply » button. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 67 Level 7 load balancing Adding virtual servers Sommaire Push this new configuration to the peer ALOHA (cluster mode) by clicking on the « push » button (be sure to try before synchronizing). © Copyright Exceliance 2007-2009 - - www.exceliance.fr 68 Level 7 load balancing Adding virtual servers Sommaire The « Monitoring » tab will then show you your new virtual server along with the associated real servers. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 69 Level 7 load balancing Stopping virtual servers Sommaire In case of a virtual server failure, an alert will be raised : At virtual server level At real server level © Copyright Exceliance 2007-2009 - - www.exceliance.fr 70 Level 7 load balancing Schema update Sommaire Datacenter ALB-VA 192.168.0.155 WebSRV4 192.168.0.204 WebSRV 192.168.0.201 WebSRV2 192.168.0.202 WebSRV5 192.168.0.205 Aloha Master WebSRV3 192.168.0.203 192.168.0.254 VirtualSRV2 VirtualSRV Users site © Copyright Exceliance 2007-2009 - - www.exceliance.fr 71 Level 7 load balancing Adding a real server Sommaire To add a real server in a virtual server farm, you may : Select the line of an existing real server, Cut & paste this line, Modify the values (name, IP,…). Validate your changes by clicking « OK ». Apply the configuration by clicking « Apply ». Test your config, Then push your config to the peer ALOHA when in cluster mode. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 72 Level 7 load balancing Adding a real server Sommaire The « Monitoring » tab will show you your new real server « WebSRV3 » in the virtual server farm « VirtualSRV ». © Copyright Exceliance 2007-2009 - - www.exceliance.fr 73 Level 7 load balancing Stopping a real server Sommaire In case of a real server failure or unavailability, an alert will show : At real server level. At virtual server level. 74 © Copyright Exceliance 2007-2009 - - www.exceliance.fr Level 7 load balancing Session persistence (cookies) Sommaire A session is defined as a group of HTTP requests between a client and a server in a defined period of time. This concept allows to associate a group of requests then matching it to a single client. Aloha Cookie persistence is used to maintain a link between all the requests of a given session. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 75 Level 7 load balancing Session persistence (cookies) Sommaire On the first request, the ALOHA inserts a server ID in a cookie sent to the client. With this ID, the ALOHA will then know which real server to use for all the Aloha requests in this session. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 76 Level 7 load balancing Schema update Sommaire StaticSRV1 192.168.0.206 ImageSRV StaticSRV2 192.168.0.207 Datacenter WebSRV 192.168.0.201 ALB-VA 192.168.0.155 WebSRV2 192.168.0.202 WebSRV4 192.168.0.204 Aloha Master WebSRV3 192.168.0.203 WebSRV5 192.168.0.205 192.168.0.254 VirtualSRV VirtualSRV2 Users site © Copyright Exceliance 2007-2009 - - www.exceliance.fr 77 Level 7 load balancing Content switching Sommaire Activating Content switching feature requires to setup an ACL ( here called « statics ») for the frontend. Requets analysis will take place at application level based on criterias you define. In this example, we will analyze URL content to find some subdirectories names like « images, css or js ». These criterias may be : File extensions : htm, pdf, doc, jpg, gif… subdirectories : images, css, js… Host names : extranet, intranet… IP addresses, ports, cookies, URL parameters,… © Copyright Exceliance 2007-2009 - - www.exceliance.fr 78 Level 7 load balancing Content switching Sommaire The « monitoring » tab will show you your new static servers created in a new backend (dedicated to static images). 3/3 2/2 2/2 © Copyright Exceliance 2007-2009 - - www.exceliance.fr 79 Level 7 load balancing SSL setup Sommaire In the « SSL » tab, a notification message tells you that the « stunnel » is not running. You may then configure a dedicated listen IP address:port which will be binded to the SSL certificate. To create your certificate (either from scratch or to import an existing key), click on the « New » button. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 80 Level 7 load balancing SSL setup Sommaire In this step, the wizard allows you to : Generate a private key from scratch. Or Import (upload) an existing private key file. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 81 Level 7 load balancing SSL setup Sommaire We complete the fields for the certificate request. Or We upload an existing certificate request. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 82 Level 7 load balancing SSL setup Sommaire We may auto-sign the request while waiting an official certificate (Verisign, Thawte,…), Or We upload an existing trusted certificate. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 83 Level 7 load balancing SSL setup Sommaire New certificate is then created It can be edited or deleted. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 84 Level 7 load balancing SSL setup Sommaire While editing you may : Change the certificate (requires an update by clicking on the « update » button). Sign a trusted certificate by clicking on the « Re-Sign » button. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 85 Level 7 load balancing SSL setup Sommaire This section is used to define SSL parameters (stunnel service). These parameters should not have to be modified. « chroot » defines the directory where the stunnel process will run « setuid » defines the user who will own the stunnnel daemon. « setgid » defines the user group who will own the stunnel daemon « pid » defines the « pid » file path. « debug » defines debugging level (e.g. 2 for critical, 3 for errors,…). © Copyright Exceliance 2007-2009 - - www.exceliance.fr 86 Level 7 load balancing SSL setup Sommaire This section is used to define SSL configuration parameters. « socket » specifies parameters for accept, local and remote sockets. « TIMEOUTconnect » defines wait delay before connecting to a server « TIMEOUTbusy » defines wait delay before receiving data. « TIMEOUTidle » defines connection last time when idle « TIMEOUTclose » defines wait delay before closing a connection © Copyright Exceliance 2007-2009 - - www.exceliance.fr 87 Level 7 load balancing SSL setup Sommaire This section is used to define SSL configuration parameters. « client » indicates if SSL service will run in remote SSL mode (client) or server mode « key » private key file path « cert » certificate file path « accept » defines on which IP address:port « HA Proxy » will accept connections « connect » defines remote host name:port © Copyright Exceliance 2007-2009 - - www.exceliance.fr 88 Level 7 load balancing SSL setup Sommaire An example of a configured section © Copyright Exceliance 2007-2009 - - www.exceliance.fr 89 Level 7 load balancing SSL setup Sommaire After having configured the SSL section, you must go to the « LB Layer7 » tab to modify the corresponding virtual server (frontend section). You need to add the IP address which will be used by « stunnel » service (as previously configured in the SSL setup). © Copyright Exceliance 2007-2009 - - www.exceliance.fr 90 Level 4 load balancing Schema update Sommaire Datacenter Director ImagesSRV SslRProxy1 192.168.0.101:443 StaticSRV1 192.168.0.206 SslRProxy2 192.168.0.102:443 StaticSRV2 192.168.0.207 WebSRV 192.168.0.201 WebSRV2 192.168.0.202 192.168.0.254 WebSRV3 192.168.0.203 Aloha Master ALB-VA 192.168.0.155 VirtualSRV WebSRV4 192.168.0.204 WebSRV5 192.168.0.205 VirtualSRV2 Users site © Copyright Exceliance 2007-2009 - - www.exceliance.fr 91 Level 4 load balancing Network flows Sommaire In the « Flows » tab, a notification message tells that the service is not running. To start it, go to the « Services » tab and start it up in automatic mode. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 92 Level 4 load balancing Network flows Sommaire Now, you have to identify the network flows that will be treated The « Flow » keyword is used to evaluate a flow rule Strategies : « permit » indicates that the evaluated flow is immediately accepted. « deny » indicates that the evaluated flow is immediately blocked. « director »indicates that the evaluated flow will be marked with the director’s name who defines the applied load balancing rules. Rules evaluation & ignorance: « match » evaluates if a packet matches the conditions. If so, the defined strategy is applied then the following rule is evaluated « ignore » evaluates if a packet matches the conditions. If so, strategy will not be applied but packet will be evaluated in the next rule. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 93 Level 4 load balancing Network flows Sommaire Now, you define the rules that will be used to treat the matching flow Conditions : « proto » defines the type of IP protocol : tcp, udp or icmp. « iface » defines the network incoming interface « src » defines the source IP of the packet or its network mask « dst » defines the destination IP adress or network mask for the packet « srcport » defines the source ports of the packet « dstport » defines the destination port of the packet « icmptype » defines the ‘icmp’ code type of the packet. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 94 Level 4 load balancing Configuration (LB Layer4) Sommaire On the « LB Layer4 » tab, a notification message tells that the « LVS » service is not running. You may go to the « Services » tab and activate it along with the « Ipforward » service in automatic mode (as shown on the left). To do this, click on the « setup » buttin and replace the keyword ‘no autostart’ by ‘autostart’ (just delete ‘no’). Submit your configuration by clicking on « OK », then « Close ». Once on the original « services » tab, click on the « apply » button of these 2 services to apply your changes. Now, you have to create a new «LB L4 » configuration as explained below. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 95 Level 4 load balancing Directors configuration Sommaire This section is dedicated to the L4 directors load balancing configuration. « balance » defines which load balancing algorythm will be used. « roundrobin » will use each real server in a round robin way using server’s weight. A (Weight =1) B (W =1) A (W =1) B (W =1) A (W =2) (W =2) Identical weights © Copyright Exceliance 2007-2009 - A B (W =1) A (W =2) A (W =2) B (W =1) Different weights - www.exceliance.fr 96 Level 4 load balancing Directors configuration Sommaire This section is dedicated to the L4 directors load balancing configuration. « leastconn » ALOHA will choose the server who manage the lowest number of connections A (Connections=10) A B (C=5) © Copyright Exceliance 2007-2009 - (New connection) - www.exceliance.fr (C=10) B n=6) (C=6) 97 Level 4 load balancing Directors configuration Sommaire This section is dedicated to the L4 directors load balancing configuration. « balance source »: ALOHA will use a source client IP hash to always connect the client on the same real server. PC1 IP=64.3.1.150 PC1 A PC2 PC2 IP=86.30.5.12 B © Copyright Exceliance 2007-2009 - - www.exceliance.fr 98 Level 4 load balancing Directors configuration Sommaire This section is dedicated to the L4 directors load balancing configuration. « balance dest »: The director will always match the same server to the same client using a destination IP hash divided by the total weight of all the active servers. PC1 IP=64.3.1.150 PC1 A PC2 PC2 IP=86.30.5.12 B © Copyright Exceliance 2007-2009 - - www.exceliance.fr 99 Level 4 load balancing Directors configuration Sommaire This section is dedicated to the L4 directors load balancing configuration. « balance shortexpdelay »: Director will assign incoming traffic to the faster server (first to answer a request). PC1 Delay : 10 ms A PC1 Delay : 900 ms B © Copyright Exceliance 2007-2009 - - www.exceliance.fr 100 Level 4 load balancing Directors configuration Sommaire This section is dedicated to the L4 directors load balancing configuration. « balance neverqueue » Director will assign incoming traffic to the first available server if any, if not, will use the shortest expected delay algorythm. A PC1 PC2 Traitement en cours… Disponible B © Copyright Exceliance 2007-2009 - - www.exceliance.fr 101 Level 4 load balancing Directors configuration Sommaire This section is dedicated to the L4 directors load balancing configuration. « mode gateway » used by direct routing mode. « mode nat » used when needing a destination network address translation « mode tunnel » used for IP in IP encapsulation mode « option persistence » defines if a director service will use persistence or not. One client requests will always be directed to the same server as it was selected for the first request. « option tcpcheck » allows to healthcheck a server opening a TCP connection on its real IP address. « server » defines real servers IP addresses or IP adresses:ports pairs. « weight » gives a weight to a real server (will be used by weighted algorythms) « check » activates check on server’s status. « sorry » defines a ‘sorry’ server who will be used if all the real servers become unavailable. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 102 Level 4 load balancing Directors configuration Sommaire Your directors configuration will be shown on the « monitor » tab. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 103 High availability VRRP between two ALOHA Sommaire Datacenter Aloha Master Site de production VRRP Aloha Backup Aloha Backup VRRP Aloha Master Site des utilisateurs Datacenter Users site Aloha Master VRRP Aloha Backup Users site © Copyright Exceliance 2007-2009 - - www.exceliance.fr 104 High availability VRRP between two ALOHA Sommaire To configure ALOHA high availability with VRRP you need to : Go to the « Services » tab and edit the « vrrp » service configuration by clicking on the « setup » button. Indicates which network interfaces will be part of the VRRP service. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 105 High availability VRRP between two ALOHA Sommaire Then, you need to : Edit service « network ethX » configuration (where X is the interface number(s) used in the VRRP service) by clicking on the « setup » button. Then define VRRP parameters © Copyright Exceliance 2007-2009 - - www.exceliance.fr 106 High availability Configuration synchronization Sommaire To configure the settings synchronization between 2 ALOHA you need to : Go to the « Services » tab and click on the [advanced mode] link (at the bottom of the services icons list). Edit parameters by clicking on the « edit » button. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 107 High availability Configuration synchronization Sommaire You also need to : Define IP addresses and few other settings. Click on the « OK » button then the « Close » button. Validate by clicking on « genkey », then « start » and « getkey » button. Important : This procedure needs to be done on the 2 ALOHA. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 108 Monitoring Sommaire Status : UP (green) : backend or frontend is fully operational or real server positively respond to healthchecks. UP (orange) : the server failed to an healthcheck , its status may switch to DOWN if more checks are failing. DOWN (red) : server did not respond to healthchecks or a backend is unoperational because all its real servers are down. DOWN (orange) : server was down but now responds to healthchecks. its status may switch to « UP » if more checks are successful. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 109 Monitoring Sommaire OPEN (green) : frontend is fully operational. FULL (red) : frontend is saturated (maxconn). no check (grey) : no healthcheck on this server. Active/Backup: server is configured as active or backup. Active x/y : number of operational active servers / total of active servers in the backend. Backup x/y : number of operational backup servers / number of total operational servers in the backend. Connections : instant amount of connections. Queued : number of connections in queue © Copyright Exceliance 2007-2009 - - www.exceliance.fr 110 Statistics Sommaire « Status cur » : current frontend or backend status. « Status change » : duration time since last status change. « Queue cur » : number of sessions in wait queue. « Queue max » : maximum reached number of sessions in queue « Queue limit » : set limit for the max number of sessions in wait queue. « Connections cur » : current number of sessions. « Connections max » : maximum peak of simultaneous sessions. « Connections limit » : set limit for simultaneous sessions. « Connections cumul » : number of sessions counter. « Connections LoadB » : counter for load balanced sessions (not attached to one server with persistence). « Bytes In » : incoming bytes counter. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 111 Statistics Sommaire « Bytes Out » : compteur du nombre d'octets sortants. « Denied Req » : compteur du nombre de requêtes filtrées. « Denied Resp » : compteur du nombre de réponses filtrées. « Errors Conn » : compteur du nombre d'erreurs de connexions. « Errors Req » : compteur du nombre de requêtes erronées. « Error Resp » : compteur du nombre de réponses erronées. « Warnings retry » : compteur du nombre de ré-essais de connexions. « Warnings redispatch » : nombre de sessions réaffectées suite à une impossibilité de connexion. « Servers active » : nombre de serveurs actifs opérationnels sur le nombre total de serveurs actifs. « Servers backup » : nombre de serveurs backups opérationnels sur le nombre total de serveurs backups. « Down check » : compteur du nombre d'échecs du test de vitalité. « Down count » : compteur du nombre de passages à l'état « down ». « Down time » : temps total passé dans l'état « down ». © Copyright Exceliance 2007-2009 - - www.exceliance.fr 112 Events logs Sommaire System logs : This log section shows logs about ALOHA system events (services start/stop, processes and L4 load balancing events. Level 7 load balancing events : Most of the events are logged : starts, stops, servers status, connections, errors. Virtual and real servers start & stop actions are sent as notifications, stop signals as ’warnings’ and servers or services shutdown as ‘alerts’. Level 7 traffic logs: Basically, logged informations give details on client port, TCP/HTTP state counters, precise sessions states at closing, details on load balancing decisions and ability to capture arbitrary headers. Standard connections are logged at ‘info’ level. Console logs : © Copyright Exceliance 2007-2009 - - www.exceliance.fr CLI commands are shown as ‘info’, output as ‘notice’ and error output as ‘warning’. 113 FAQ Configuration error control Sommaire After configuration validation and in case there is an error , an error message will appear as shown beside. To get more details on it, just click on the ‘console log’ link. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 114 FAQ Configuration error control Sommaire After having clicked on the link, a console log window appears with focus on the last events. Error type is specified along with the related line number. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 115 FAQ Configuration error control Sommaire Just go to the indicated line number, Make the proper correction. You may find some hints by clicking on the ‘help’ link at the right top of the configuration section © Copyright Exceliance 2007-2009 - - www.exceliance.fr 116 FAQ Configuration error control Sommaire The help tells us that a « _ » was missing between the ‘use’ and’backend’ keywords. You may now validate this configuration. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 117 FAQ Configuration backup Sommaire It is important to understand that when you modify a configuration and validate it, it is only applied in memory and not directly save in the config file which is used at startup. To do this, you must click on the « Configuration not saved » link then on the « Save » button. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 118 Contact Sommaire Don’t hesitate to contact us : by mail : [email protected] By phone : +33.1.30.67.60.74 Our visit our website : www.exceliance.fr. © Copyright Exceliance 2007-2009 - - www.exceliance.fr 119