NetScaler 10.5 Link Load Balancing

Link Load Balancing2015-01-16 04:48:33 UTC © 2015 Citrix Systems, Inc. All rights reserved. Terms of Use | Trademarks | Privacy Statement Contents Link Load Balancing .......................................................................................... 3 Configuring a Basic LLB Setup .................................................................. 4 Configuring Services........................................................................ 5 Configuring an LLB Virtual Server and Binding a Service ............................. 8 Configuring the LLB Method and Persistence........................................... 11 Configuring an LLB Route.................................................................. 15 Creating and Binding a Transparent Monitor ........................................... 19 Configuring RNAT with LLB ..................................................................... 24 Configuring a Backup Route .................................................................... 26 Resilient LLB Deployment Scenario ........................................................... 29 Monitoring an LLB Setup ........................................................................ 31 2 Link Load Balancing Link load balancing (LLB) balances outbound traffic across multiple Internet connections provided by different service providers. LLB enables the Citrix® NetScaler® appliance to monitor and control traffic so that packets are transmitted seamlessly over the best possible link. Unlike with server load balancing, where a service represents a server, with LLB, a service represents a router or the next hop. A link is a connection between the NetScaler and the router. To configure link load balancing, many users begin by configuring a basic setup with default settings. Configuring a basic setup involves configuring services, virtual servers, monitors, routes, an LLB method, and, optionally, configuring persistence. Once a basic setup is operational, you can customize it for your environment. Load balancing methods that are applicable to LLB are round robin, destination IP hash, least bandwidth, and least packets. You can optionally configure persistence for connections to be sustained on a specific link. The available persistence types are source IP address-based, destination IP address-based, and source IP and destination IP address-based. PING is the default monitor but configuring a transparent monitor is recommended. You can customize your setup by configuring reverse NAT (RNAT) and backup links. 3 you first create services representing each router to the Internet Service Providers (ISPs). Then.Configuring a Basic LLB Setup To configure LLB. A PING monitor is bound by default to each service. bind the services to the virtual server. Optionally. 4 . you can configure persistence to make sure that all traffic for a particular session is sent over a specific link. and configure a route for the virtual server. The virtual server selects a router by using the load balancing method that you specify. you create a virtual server. Binding a transparent monitor is optional but recommended. The route identifies the virtual server as the gateway to the physical routers represented by the services. Configuring Services A default monitor (PING) is automatically bound to a service type of ANY when the service is created.10.10.254 Server ID : 0 Monitor Threshold : 0 Max Conn: 0 Max Req: 0 Max Bandwidth: 0 kbits Use Source IP: NO Client Keepalive(CKA): NO Access Down Service: NO TCP Buffering(TCPB): YES HTTP Compression(CMP): NO Idle timeout: Client: 120 sec Server: 120 sec Client IP: DISABLED Cacheable: NO SC: OFF SP: OFF Down state flush: ENABLED 1) Done 5 Monitor Name: ping State: UP Weight: 1 Probes: 244705 Failed [Total: 0 Current: 0] Last response: Success .ANY State: DOWN Last state change was at Tue Aug 31 04:31:13 2010 Time since last state change: 2 days.10.ICMP echo reply received. as described in " Creating and Binding a Transparent Monitor.254 any * show service ISP1R_svc_any ISP1R_svc_any (10.10. Response Time: 1. but you can replace the default monitor with a transparent monitor.600 Server Name: 10." To create a service by using the command line interface At the command prompt. 05:34:18.322 millisec .10.10. type: • add service <name> <IP> <serviceType> <port> • show service <name> Example add service ISP1R_svc_any 10.254:*) . In the details pane. Parameter Descriptions (of commands listed in the CLI procedure) add service name Name for the service. equals (=). space. colon (:). 3. To create services by using the configuration utility 1. and must contain only ASCII alphanumeric. click Add. In the Create Service dialog box. Navigate to Traffic Management > Load Balancing > Services. Click Create.Configuring Services To create services by using the configuration utility Navigate to Traffic Management > Load Balancing > Services. serviceType Protocol in which data is exchanged with the service. 2.). hash (#). Click Close. specify values for the following parameters: • Service Name*—name • Server—IP • Protocol*—serviceType (Select ANY from the drop-down list. and hyphen (-) characters. Repeat Steps 2-4 to create another service. 6 . Must begin with an ASCII alphabetic or underscore (_) character.) • Port*—port * A required parameter 4. IP IP to assign to the service. 5. at (@). 6. select the services that you just configured and verify that the settings displayed at the bottom of the screen are correct. 7. and create a service. Cannot be changed after the service has been created. In the Services pane. period (. underscore. UDP. TFTP port Port number of the service. DIAMETER. SNMP. RPCSVR. DHCPRA.Configuring Services Possible values: HTTP. View description(s) in command reference Top show service name Name of the service for which to display configuration details. RTSP. View description(s) in command reference Top 7 . SSL_DIAMETER. FTP. ORACLE. DNS. SSL_BRIDGE. NNTP. ADNS_TCP. SSL_TCP. MSSQL. MYSQL. DTLS. SSL. RADIUS. TCP. DNS_TCP. RDP. ADNS. SIP_UDP. ANY. of Bound Services : 1 (Total) 0 (Active) Configured Method: ROUNDROBIN Mode: IP Persistence: NONE Connection Failover: DISABLED 1) ISP1R_svc_any (10.254: *) . 17:51:46. For information about changing the LB method.ANY State: DOWN Done 8 Weight: 1 .10. see " Configuring the LLB Method and Persistence.0.0:0) .10. The default LB method of least connections is not supported in LLB. type: • add lb vserver <name> <serviceType> • bind lb vserver < name> <serviceName> • show lb vserver < name> Example add lb vserver Router1-vip any bind lb vserver Router-vip ISP1R_svc_any sh lb vserver router-vip Router-vip (0." To create a link load balancing virtual server and bind a service by using the command line interface At the command prompt.0.ANY Type: ADDRESS State: DOWN Last state change was at Thu Sep 2 10:51:32 2010 Time since last state change: 0 days.770 Effective State: DOWN Client Idle Timeout: 120 sec Down state flush: ENABLED Disable Primary Vserver On Down : DISABLED No. create a virtual server and bind services to the virtual server.Configuring an LLB Virtual Server and Binding a Service After you create a service. 2. equal sign (=).Configuring an LLB Virtual Server and Binding a Service To create a link load balancing virtual server and bind a service by using the configuration utility 1. DNS. UDP. PUSH. TFTP. DTLS. at sign (@). hash (#). space. enclose the name in double or single quotation marks (for example. Specify ANY in the Protocol field. RTSP. equal sign (=). and hyphen (-) characters. in the Active column. Note: Make sure that Directly Addressable is unchecked. SSL_BRIDGE. DNS_TCP. RDP. serviceType Protocol used by the service (also called the service type). colon (:). SSL_TCP. ORACLE View description(s) in command reference Top bind lb vserver name Name for the virtual server. Parameter Descriptions (of commands listed in the CLI procedure) add lb vserver name Name for the virtual server. select the check box for the service that you want to bind to the virtual server. Possible values: HTTP. DHCPRA. Under the Services tab. SSL. hash (#). Can be changed after the virtual server is created. RADIUS. NNTP. at sign (@). TCP.). enclose the name in double or single quotation marks (for example. FTP.). and must contain only ASCII alphanumeric. CLI Users: If the name includes one or more spaces. DIAMETER. Must begin with an ASCII alphanumeric or underscore (_) character. Must begin with an ASCII alphanumeric or underscore (_) character. underscore. and must contain only ASCII alphanumeric. period (. Navigate to Traffic Management > Load Balancing > Virtual Servers. ANY. period (. and hyphen (-) characters. SSL_PUSH. Can be changed after the virtual server is created. and create a virtual server for link load balancing. MYSQL. SIP_UDP. serviceName 9 . space. colon (:). SSL_DIAMETER. MSSQL. underscore. "my vserver" or 'my vserver'). "my vserver" or 'my vserver'). CLI Users: If the name includes one or more spaces. View description(s) in command reference Top 10 . statistical data of all configured virtual servers is displayed. If no name is provided. View description(s) in command reference Top show lb vserver name Name of the virtual server.Configuring an LLB Virtual Server and Binding a Service Name of the service. 255. the NetScaler appliance uses the least connections method to select the service for redirecting each client request.0:0) . You can also configure persistence.ANY Type: ADDRESS State: DOWN Last state change was at Fri Sep 3 04:46:48 2010 Time since last state change: 0 days.Configuring the LLB Method and Persistence By default.255.0. so that different transmissions from the same client are directed to the same server. type the following command: • set lb vserver <name> -lbMethod <lbMethod> -persistenceType <persistenceType> • show lb vserver <name> Example set lb vserver router-vip -lbmethod ROUNDROBIN -persistencetype SOURCEIP show lb vserver Router-vip Router-vip (0. but you should set the LLB method to one of the supported methods.200 Effective State: DOWN Client Idle Timeout: 120 sec Down state flush: ENABLED Disable Primary Vserver On Down : DISABLED No.0. 00:52:21. of Bound Services : 0 (Total) 0 (Active) Configured Method: ROUNDROBIN Mode: IP Persistence: SOURCEIP Persistence Mask: 255. To configure the LLB method and/or persistence by using the command line interface At the command prompt.255 Persistence v6MaskLength: 128 Persistence Timeout: 2 min Connection Failover: DISABLED 11 . Also available are a number of hashing methods. In the Advanced section. lbMethod Load balancing method. Response times are learned through monitoring probes. regardless of the load. The available settings function as follows: * ROUNDROBIN . If it finds a match. In the Advanced section.Distribute requests in rotation. * LEASTPACKETS .Select the service currently serving the lowest number of packets per second. select Method and configure the load balancing method.Configuring the LLB Method and Persistence To configure the link load balancing method and/or persistence by using the configuration utility 1. Weights can be assigned to services to enforce weighted round robin distribution. * LRTM . * LEASTRESPONSETIME .Base service selection on the SNMP metrics obtained by custom load monitors. 12 . creates a hash of the portion.Select the service with the lowest average response time. Navigate to Traffic Management > Load Balancing > Virtual Servers and select the virtual server for which you want to configure the load balancing method and/or persistence settings.Select the service with the lowest response time. Following are the hashing methods: * URLHASH . Parameter Descriptions (of commands listed in the CLI procedure) set lb vserver name Name of the virtual server.Select the service currently handling the least traffic. * CUSTOMLOAD . This method also takes the number of active connections into account. * LEASTCONNECTION (default) .Create a hash of the request URL (or part of the URL). select Persistence and configure the persistence parameters.Select the service with the fewest connections. 3. 2. and then checks whether any previous requests had the same hash value. it forwards the request to the service that served those previous requests. in which the appliance extracts a predetermined portion of the request. * LEASTBANDWIDTH . SRCIPDESTIPHASH. * SRCIPDESTIPHASH . * TOKEN . belong to the same persistence session.Requests that have the same server ID in the URL query belong to the same persistence session.Create a hash of the destination IP address in the IP header. * COOKIEINSERT . * DESTINATIONIPHASH . * RULE . Available settings function as follows: * SOURCEIP .Connections from the same client IP address belong to the same persistence session.Create a hash of the SIP Call-ID header.All connections that match a user defined rule belong to the same persistence session.Create a hash of the source IP address in the IP header.Create a hash of the string obtained by concatenating the source IP address and destination IP address in the IP header. * CUSTOMSERVERID . If the request does not contain a domain name. The server ID is the hexadecimal representation of the IP address and port of the service to which the request must be forwarded. LEASTRESPONSETIME. LEASTREQUEST Default value: PEMGMT_LB_LEASTCONNS persistenceType Type of persistence for the virtual server. The domain name is taken from either the URL or the Host header. SOURCEIPHASH.Create a hash of the domain name in the request (or part of the domain name).Connections that have the same SSL Session ID belong to the same persistence session. * URLPASSIVE . CUSTOMLOAD. * CALLIDHASH . LRTM.Connections to the same destination IP address belong to the same persistence session. and then select the service to which any previous requests with the same token hash value were sent.Connections with the same server ID form part of the same session. the URL is preferred.Configuring the LLB Method and Persistence * DOMAINHASH . TOKEN. DOMAINHASH. LEASTCONNECTION. LEASTBANDWIDTH. set the Server ID (CustomServerID) parameter for each service and configure the Rule parameter to identify the server ID in a request.Create a hash of the source IP address and source port in the IP header. the load balancing method defaults to LEASTCONNECTION. DESTINATIONIPHASH. LEASTPACKETS. inserted by a Set-Cookie directive from a server. URLHASH. create a hash of the token. * DESTIP . This persistence type requires a rule to identify the server ID in the request. * SOURCEIPHASH . Possible values: ROUNDROBIN.Extract a token from the request.Connections that have the same HTTP Cookie. If the domain name appears in both locations. * SRCIPSRCPORTHASH . SRCIPSRCPORTHASH. For this persistence type. CALLIDHASH. 13 . * SSLSESSION . DIAMETER. SSLSESSION. * RTSPSID .Connections that have the same RTSP Session ID belong to the same persistence session. statistical data of all configured virtual servers is displayed. COOKIEINSERT. RTSPSID. SRCIPDESTIP. NONE View description(s) in command reference Top show lb vserver name Name of the virtual server. CUSTOMSERVERID. DESTIP. CALLID. Possible values: SOURCEIP. * CALLID .Connections that have the same CALL-ID SIP header belong to the same persistence session. RULE.Configuring the LLB Method and Persistence * SRCIPDESTIP . URLPASSIVE.Connections that have the same source IP address and destination IP address belong to the same persistence session. View description(s) in command reference Top 14 . If no name is provided. type: • add lb route <network> <netmask> <gatewayName> • show lb route [<network> <netmask>] Example add lb route 0.0 0.0.0.0 Router-vip show lb route 0.--------------------1) 0.0 Router-vip UP To configure an IPv6 LLB route by using the command line interface At the command prompt.0 0. you configure an IPv4 or IPv6 LLB route for the network specifying the virtual server as the gateway.0.0. Requests are sent to the virtual server IP address that acts as the gateway for all outbound traffic and selects the router based on the LLB method configured.0. LLB methods. To configure an IPv4 LLB route by using the command line interface At the command prompt.Configuring an LLB Route After configuring the IPv4 or IPv6 services.0.0 Network Netmask Gateway/VIP Flags ----------------------.0. virtual servers.0.0. and persistence. type: • add lb route6 <network> <gatewayName> • show lb route6 add lb route6 ::/0 llb6_vs show lb route6 Network VIP ------------------1) ::/0 llb6_vs 15 Flags -------UP .0. A route is a collection of links that are load balanced.0.0.0 0. and select LLB. In the details pane. Navigate to System > Network > Routes. and configure the LLB route. To configure an LLB route by using the configuration utility 1. Click LLBV6 to configure an IPv4 route. set the following parameters: • • Network* • Netmask*—Required for IPV4 routes. 2. Click Create. 3. and then click Close. 16 . Note: Select LLBV6 to configure an IPV6 route. A service is configured for each of the two links (ISPs) and PING monitors are bound by default to these services. The following diagram shows a basic LLB setup. The route that you just created appears on the LLB or the LLB6 tab in the Routes pane. A link is selected based on the LLB method configured. Gateway Name*—gatewayName * A required parameter • 4.Configuring an LLB Route Example To configure an LLB route by using the configuration utility Navigate to System > Network > Routes. select one of the following: • Click LLB to configure an IPv4 route. In the Create LB Route or Create LB IPV6 Routedialog box. replace the IPv4 service with an IPv6 service in the above figure. Basic LLB Setup Note: If your Internet service provider has provided an IPv6 address. netmask The netmask to which the route belongs. gatewayName 17 . Parameter Descriptions (of commands listed in the CLI procedure) add lb route network The IP address of the network to which the route belongs.Configuring an LLB Route Figure 1. View description(s) in command reference Top add lb route6 network The destination network.Configuring an LLB Route The name of the route. gatewayName The name of the route. View description(s) in command reference Top show lb route6 No parameters provided in this topic or the command has no parameters. View description(s) in command reference Top 18 . View description(s) in command reference Top show lb route network The destination network or host. .....: NO Transparent.: 1 Failure Retries.: 0 sec Destination IP........10...: ENABLED Action....11 -transparent YES > show lb monitor monitor-1 1) Name... You can then bind the transparent monitor to services.10......... the packet is not delivered to the final destination because one of the next hop devices is down... the appliance includes the router while performing load balancing and forwards the packet to the router.: monitor-1 Type........... The transparent monitor monitors all the devices existing in the path from the appliance to the device that owns the destination IP address specified in the monitor.......: 0 19 ...: Not applicable Deviation..: 5 sec Retries.... The default PING monitor monitors the connectivity only between the NetScaler appliance and the upstream device... if any of the devices (including the router) are down.......Creating and Binding a Transparent Monitor You create a transparent monitor to monitor the health of upstream devices. If a transparent monitor is not configured and the status of the router is UP but one of the next hop devices from that router is down... such as routers...........: 10.....10..........: ENABLED Standard parameters: Interval. the service is marked as DOWN and the router is not included when the appliance performs link load balancing...: NO TOS ID.......11 Destination port. By binding a transparent monitor...: 30 sec Reverse......10........: 3 Response timeout... However.........: 2 sec Down time.: 0 SNMP Alert Retries: 0 Success Retries. type: • add lb monitor <monitorName> <type> -destIP <ip_addr|*> -transparent YES • show lb monitor [<monitorName>] Example add lb monitor monitor-1 PING -destIP 10.. To create a transparent monitor by using the command line interface At the command prompt..: PING State...: NO LRTM..: Bound service Iptunnel.......: NO TOS..: YES Secure..... type: • bind lb monitor <monitorName> <serviceName> • show service <name> Example 20 . and then click Add. select the monitor that you just configured and verify that the settings displayed in the Details pane are correct. 3. and then click Close. 2. In the Create Monitor dialog box. Click Create.Creating and Binding a Transparent Monitor To create a transparent monitor by using the configuration utility Navigate to Traffic Management > Load Balancing > Monitors and configure a transparent monitor. In the Monitors pane. under Available. In the Monitors pane. set the following parameters: • Name* • Type* • Destination IP • Transparent * A required parameter 4. 5. On the Monitors tab. To bind a monitor to a service by using the command line interface At the command prompt. Navigate to Traffic Management > Load Balancing > Monitors. To create a transparent monitor by using the configuration utility 1. 2. select the monitor that you want to bind to the service. click Add. To bind a monitor to a service by using the configuration utility 1. Navigate to Traffic Management > Load Balancing > Services. In the Configure Service dialog box. 4.10. under Available. 5.10.254:*) . 2. 3. In the Services pane. and then click Add. select the service that you just configured and verify that the settings displayed in the Details pane are correct. Click OK. select a service to which you want to bind a monitor.ANY State: UP Last state change was at Thu Sep 2 10:51:07 2010 Time since last state change: 0 days. Navigate to Traffic Management > Load Balancing > Services.322 millisec Done To bind a monitor to a service by using the configuration utility 1. 21 . on the Monitors tab.10. In the details pane. select the monitor that you want to bind to the service.ICMP echo reply received.254 Server ID : 0 Monitor Threshold : 0 Max Conn: 0 Max Req: 0 Max Bandwidth: 0 kbits Use Source IP: NO Client Keepalive(CKA): NO Access Down Service: NO TCP Buffering(TCPB): YES HTTP Compression(CMP): NO Idle timeout: Client: 120 sec Server: 120 sec Client IP: DISABLED Cacheable: NO SC: OFF SP: OFF Down state flush: ENABLED 1) Monitor Name: monitor-HTTP-1 State: UP Weight: 1 Probes: 1256 Failed [Total: 0 Current: 0] Last response: Success . 18:41:55. Response Time: 1.130 Server Name: 10.10. and then click Open.Creating and Binding a Transparent Monitor bind lb monitor monitor-HTTP-1 isp1R_svc_any Done > show service isP1R_svc_any ISP1R_svc_any (10. underscore. SMTP. DNS. The state of a transparent device depends on the responsiveness of the services behind it. CITRIX-XML-SERVICE. NNTP. CITRIX-XDM destIP IP address of the service to which to send probes. the IP address of the server to which the monitor is bound is considered the destination IP address. HTTP-ECV. a destination IP address must be specified. RADIUS. RADIUS_ACCOUNTING. SIP-UDP. DIAMETER. FTP. "my monitor" or 'my monitor'). POP3. MYSQL-ECV. MSSQL-ECV. equals (=). colon (:). LDAP.). If a transparent device is being monitored. period (. Possible values: YES. FTP-EXTENDED. at (@). STOREFRONT. View description(s) in command reference Top 22 . MYSQL. space. CITRIX-AAC-LOGINPAGE. Must begin with an ASCII alphanumeric or underscore (_) character. LDNS-TCP. CITRIX-WEB-INTERFACE. The probe is sent to the specified IP address by using the MAC address of the transparent device. LDNS-PING. NO Default value: NO View description(s) in command reference Top show lb monitor monitorName Name of the monitor. CLI Users: If the name includes one or more spaces.Creating and Binding a Transparent Monitor Parameter Descriptions (of commands listed in the CLI procedure) add lb monitor monitorName Name for the monitor. hash (#). Possible values: PING. CITRIX-XD-DDC. HTTP-INLINE. HTTP. CITRIX-WI-EXTENDED. APPC. TCP. CITRIX-XNC-ECV. CITRIX-AG. LDNS-DNS. transparent The monitor is bound to a transparent device such as a firewall or router. TCP-ECV. type Type of monitor that you want to create. USER. ND6. ARP. If the parameter is set to 0. SNMP. LOAD. DNS-TCP. RTSP. ORACLE-ECV. CITRIX-AAC-LAS. UDP-ECV. enclose the name in double or single quotation marks (for example. and must contain only ASCII alphanumeric. and hyphen (-) characters. View description(s) in command reference Top show service No parameters provided in this topic or the command has no parameters.Creating and Binding a Transparent Monitor bind lb monitor monitorName Name of the monitor. View description(s) in command reference Top 23 . serviceName Name of the service or service group. 0 > show rnat 1) Network: 10. This ensures that the return network traffic for a specific flow is routed through the same path.0 NatIP: * To configure RNAT by using the configuration utility 1. Specify the network on which to perform RNAT.29. On the RNAT tab. You must then enable use subnet IP (USNIP) mode. To configure RNAT by using the command line interface At the command prompt.102.255.Configuring RNAT with LLB You can configure an LLB setup for reverse network address translation (RNAT) for outbound traffic. from the Actions drop-down list.255. type: • enable ns mode USNIP • show ns mode Example 24 . and then configure RNAT.102.0 255.255.255. 3. select Configure RNAT. as described in " Configuring a Basic LLB Setup".0 Netmask: 255. First configure basic LLB. type: • set rnat <network> <netmask> • show rnat Example set rnat 10. Navigate to System > Network > Routes. 2.29. To enable Use Subnet IP mode by using the command line interface At the command prompt. click Configure Modes. View description(s) in command reference Top show rnat No parameters provided in this topic or the command has no parameters. View description(s) in command reference Top enable ns mode No parameters provided in this topic or the command has no parameters. and then click OK. Navigate to System > Settings and. In the Configure Modes dialog box. select Use Subnet IP. 2. View description(s) in command reference Top show ns mode No parameters provided in this topic or the command has no parameters. under Modes and Features. 8) Use Subnet IP 9) … Acronym ------FR Status -----ON USNIP ON To enable Use Subnet IP mode by using the configuration utility 1. Parameter Descriptions (of commands listed in the CLI procedure) set rnat network IPv4 network address on whose traffic you want the NetScaler appliance to do RNAT processing.Configuring RNAT with LLB enable ns mode USNIP > show ns mode Mode ------1) Fast Ramp 2) …. View description(s) in command reference Top 25 . Once the backup route is configured. Router-vip is the primary virtual server. you can configure a backup route. 26 . First create a primary virtual server as described in "Configuring an LLB Virtual Server and Binding a Service.Configuring a Backup Route To prevent disruption in services when the primary route is down. create a secondary virtual server similar to a primary virtual server and then designate this virtual server as a backup virtual server (route). Backup Route Setup Note: If your Internet service provider has provided an IPv6 address. when the primary route fails. and Backup_Router-vip is the secondary virtual server designated as the backup virtual server. However. replace the IPv4 service with an IPv6 service in the above figure. In the following diagram. the NetScaler appliance automatically uses it when the primary route fails." To configure a backup route. By default. all traffic is sent through the primary route. all traffic is diverted to the backup route as shown in the following diagram. Figure 1. of Bound Services : 1 (Total) 1 (Active) 27 . To set the secondary virtual server as the backup virtual server by using the command line interface At the command prompt. Backup Routing in Operation Note: If your Internet service provider has provided an IPv6 address.600 Effective State: UP Client Idle Timeout: 120 sec Down state flush: ENABLED Disable Primary Vserver On Down : DISABLED No.0:0) . 03:09:45. type: set lb vserver <name> -backupVserver <string> Example set lb vserver Router-vip -backupVServer Backup_Router-vip > show lb vserver Router-vip Router-vip (0.0.0.ANY Type: ADDRESS State: UP Last state change was at Fri Sep 3 04:46:48 2010 Time since last state change: 0 days. replace the IPv4 service with an IPv6 service in the above figure.Configuring a Backup Route Figure 2. In the Load Balancing Virtual Server dialog box. under Advanced. and then click OK. Navigate to Traffic Management > Load Balancing > Virtual Servers and select the secondary virtual server for which you want to configure the backup virtual server.255.255 Backup: Router2-vip Connection Failover: DISABLED Done Persistence v6MaskLength: 128 Persisten To set the secondary virtual server as the backup virtual server by using the configuration utility 1. 2. In the Backup Virtual Server drop-down list. backupVserver Name of the backup virtual server to which to forward requests if the primary virtual server goes DOWN or reaches its spillover threshold.255. View description(s) in command reference Top 28 . select Protection. 3. Parameter Descriptions (of commands listed in the CLI procedure) set lb vserver name Name of the virtual server. select the secondary backup virtual server.Configuring a Backup Route Configured Method: ROUNDROBIN Mode: IP Persistence: DESTIP Persistence Mask: 255. Router1-vip for ISP1 is DOWN.30 is sent through Router1-vip and traffic with the destination IP specified as 30. there are two networks: 30. Link load balancing is configured based on the destination IP address.Resilient LLB Deployment Scenario In the following diagram.31.30.30. Router1-vip is configured as a backup to Router2-vip and vice versa.30.31 is sent through Router2-vip.0 and 30. so all traffic with the destination IP specified as 30.30.30. 29 . replace the IPv4 service with an IPv6 service in the above figure. However. respectively. if any one of the gateways (Router1-vip or Router2-vip) is DOWN.0.30. Figure 1.31. In the following diagram. Resilient LLB Deployment Setup Note: If your Internet service provider has provided an IPv6 address.30 is also sent through ISP2. traffic is routed through the backup router.30.30. All traffic with the destination IP specified as 30. Two routes are configured with gateways Router1-vip and Router2-vip. Resilient LLB Deployment Scenario Note: If your Internet service provider has provided an IPv6 address. 30 .Resilient LLB Deployment Scenario Figure 2. replace the IPv4 service with an IPv6 service in the above figure. You can display the following details: • Name • IP address • Port • Protocol • State of the virtual server • Rate of requests received • Rate of hits To display virtual server statistics by using the command line interface To display a summary of the statistics for all the virtual servers currently configured on the NetScaler.102. Viewing the Statistics of a Virtual Server To evaluate the performance of virtual servers or to troubleshoot problems.Monitoring an LLB Setup After the configuration is up and running. type: stat lb vserver [-detail] [<name>] Example >stat lb vserver -detail Virtual Server(s) Summary vsvrIP port Protocol State Req/s Hits/s One * 80 HTTP UP 5/s 0/s Two * 0 TCP DOWN 0/s 0/s Three * 2598 TCP DOWN 0/s 0/s dnsVirtualNS 10. you can display details of the virtual servers configured on the NetScaler appliance.102. You can display a summary of statistics for all the virtual servers.10. you should view the statistics for each service and virtual server to check for possible problems. or you can specify the name of a virtual server to display the statistics only for that virtual server.66 80 HTTP UP 0/s 0/s Done 31 .1 80 HTTP DOWN 0/s 0/s LBVIP 10.29.29. at the command prompt. or for a single virtual server.90 53 DNS DOWN 0/s 0/s BRVSERV 10.1. select the virtual server. Navigate to Traffic Management > Load Balancing > Services > Statistics. and click Statistics. Viewing the Statistics of a Service You can view the rate of requests. 2. If you want to display the statistics for only one service. and so forth using the service statistics. Navigate to Traffic Management > Load Balancing > Virtual Servers > Statistics.Monitoring an LLB Setup To display virtual server statistics by using the configuration utility 1. requests in surge queue. If you want to display the statistics for only one virtual server. request bytes. current client connections. select the service. response bytes. type: stat service <name> Example stat service Service-HTTP-1 To view the statistics of a service by using the configuration utility 1. 32 . responses. 2. and click Statistics. To view the statistics of a service by using the command line interface At the command prompt. in the details pane. current server connections. If no name is provided. View description(s) in command reference Top 33 .Monitoring an LLB Setup Parameter Descriptions (of commands listed in the CLI procedure) stat lb vserver name Name of the virtual server. View description(s) in command reference Top stat service name Name of the service. statistical data of all configured virtual servers is displayed.