ADC

Load balancing SYSLOG servers

The Citrix ADC appliance send its SYSLOG events and messages to all the configured external log servers. This results in storing redundant messages and makes monitoring difficult for system administrators. To address this issue, the Citrix ADC appliance offers load balancing algorithms that can load balance the SYSLOG messages among the external log servers for better maintenance and performance. The supported load balancing algorithms include RoundRobin, LeastBandwidth, CustomLoad, LeastConnection, LeastPackets, and AuditlogHash.

Load balancing of SYSLOG servers using the command line interface

At the command prompt, type:

  1. Add a service and specify the service type as SYSLOGTCP or SYSLOGUDP.

    add service ( | )

  2. Add a load balancing virtual server, specify the service type as SYSLOGTCP or SYSLOGUDP, and load balancing method as AUDITLOGHASH.

    add lb vserver [-lbMethod ]

  3. Bind the service to the load balancing virtual server.

    Bind lb vserver

  4. Add a SYSLOG action and specify the load balancing server name that has SYSLOGTCP or SYSLOGUDP as service type.

    add syslogaction [-lbVserverName ] [-logLevel ]

  5. Add a SYSLOG policy by specifying the rule and action.

    add syslogpolicy

  6. Bind the SYSLOG policy to the system global for the policy to take effect.

    bind system global

*Load balancing of SYSLOG servers using the GUI

  1. Add a service and specify the service type as SYSLOGTCP or SYSLOGUDP.

    Navigate toTraffic Management>Services, clickAddand selectSYLOGTCPorSYSLOGUDPas protocol.

  2. Add a load balancing virtual server, specify the service type as SYSLOGTCP or SYSLOGTCP, and load balancing method as AUDITLOGHASH.

    Navigate toTraffic Management>Virtual Servers, clickAddand selectSYLOGTCPorSYSLOGUDPas protocol.

  3. Bind the service to the load balancing virtual server.

    Navigate toTraffic Management>Virtual Servers, select a virtual server and then selectAUDITLOGHASHin theLoad Balancing Method.

  4. Add a SYSLOG action and specify the load balancing server name that has SYSLOGTCP or SYSLOGUDP as service type.

    Navigate toSystem>Auditing, clickServersand add a server by selectingLB Vserveroption inServers.

  5. Add a SYSLOG policy by specifying the rule and action.

    Navigate toSystem>Syslog, clickPoliciesand add a SYSLOG policy.

  6. Bind the SYSLOG policy to the system global for the policy to take effect.

    Navigate toSystem>Syslog, select a SYSLOG policy and clickAction, and then clickGlobal Bindingsand bind the policy to system global.

Example:

以下配置指定负载平衡of SYSLOG messages among the external log servers using the AUDITLOGHASH as load balancing method. AUDITLOGHASH method load balances the traffic based on input hash value from the audit agents. The agents are the modules which generate auditlog in a Citrix ADC appliance. For example, if an agent LSN wants to load balance auditlogs based on client IP address, LSN module generates the hash value based on clientIP and passes the hash value to auditlog module. The auditlog module sends the auditlog messages which have same hash value to the external syslog server.

The Citrix ADC appliance generates SYSLOG events and messages that are load balanced amongst the services, service1, service2, and service 3.

add service service1 192.0.2.10 SYSLOGUDP 514 add service service2 192.0.2.11 SYSLOGUDP 514 add service service3 192.0.2.11 SYSLOGUDP 514 add lb vserver lbvserver1 SYSLOGUDP -lbMethod AUDITLOGHASH bind lb vserver lbvserver1 service1 bind lb vserver lbvserver1 service2 bind lb vserver lbvserver1 service3 add syslogaction sysaction1 -lbVserverName lbvserver1 -logLevel All add syslogpolicy syspol1 ns_true sysaction1 bind system global syspol1 

Limitations:

  • The Citrix ADC appliance does not support an external load balancing virtual server load balancing the SYSLOG messages among the log servers.
Load balancing SYSLOG servers