11.2.3.2. Redundancy setting by VRRP¶
Operation Confirmed Version: | |
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Citrix Netscaler VPX Version11.0 Build67.12 Standard Edition |
Method to make the Load Balancer redundant will be introduced here.
VRRP is a redundancy protocol that makes two routers (the Load Balancers here) recognized virtually as a single router by a connected terminal and the like.
Two Load Balancers share the role in the conditions called as MASTER and BACKUP.
Connected terminals can communicate by specifying the default gateway not to the real IP address of the Load Balancer’s interface, but to the Virtual IP address created by VRRP.
Also when the firewall in Master state cannot forward packets due to any failure, the firewall in Backup state automatically shifts to Master state, so that communications from the terminal can be continued.
Note
For the restrictions, refer to “Restrictions” section of Load Balancer Service Descriptions .
Before setting up VRRP on Netscaler VPX, you need to perform ** Registering VRRP communication settings ** from the ECL2.0 customer portal.
If VRRP is set, please make sure that DHCP (address setting function) of the Logical Network is “enabled”. If the DHCP setting is Disabled, an ARP request is made with the source address 0.0.0.0 on our network. In this case, it has been confirmed that some appliances do not ARP reply. NetScaler VPX has been confirmed not to reply with Version 11.0 Build67.12 Standard Edition.
As for preempt of VRRP, keep the default (True) unchanged. With preempt made invalid, status inconsistency among the interfaces can occur, resulting in continuation of communication disconnection.
This service does not support asymmetric communication. NetScaler VPX cannot synchronize VRRP status of multiple interfaces due to product specifications. Make the configuration that the communication goes through the same route on the way to and from the way by making redundancy with VRRP only on the client side and enabling Source NAT of NetScaler VPX. If Source NAT cannot be set due to the configuration, use the preempt function to always match the status of each interface.
Presumed case for sample setting
Assume that we want to set VRRP to the interface in the client network (192.168.1.0/24) side of the two Load Balancers (VRRP-LB1, VRRP-LB2).
On the product specification of VRRP function of NetScaler VPX
If VRRP setting of NetScaler VPX is made to both interfaces of client side and server side, VRRP status (MASTER/BACKUP) of each interface cannot be synchronized.
Therefore, it is recommended to set "Preemption" to "Yes" when configuring VRRP on both the client side and the server side. Please also check the configuration guide as a setting example.
Note
For settings of SourceNAT function, refer to “Disabling SourceNAT” in Examples of Validated Setting.
Notes on VRRP Settings
VRRP-LB1 Settings¶
Setting on ECL2.0 Portal
Setting Items |
Setting value |
Interface to set |
Interface 1/1 |
Virtual IP Address |
192.168.1.20 |
VRID | 30 |
Setting in the Load Balancer (VRRP-LB1) Management Portal
Setting Items |
Setting value |
Virtual Router ID | 30 |
Priority | 200 |
Tracking | NONE |
Preemption | Check mark |
Track Interface Priority | 0 |
Interfaces bound to this vrid | Check mark |
Setting Items |
Setting value |
IP Address | 192.168.1.20 |
Netmask | 255.255.255.0 |
IP Type | Virtual IP |
Virtual Router ID | 30 |
ICMP Response | NONE |
ARP Response | NONE |
Traffic Domain | 10 (10 is mandatory) |
State | Check mark |
ARP | Check mark |
ICMP | Check mark |
Virtual Server | Check mark |
Enable Management Access control to support the below listed applications | Check mark |
SNMP | Check mark |
VRRP-LB2 Settings¶
Setting on ECL2.0 Portal
In the scenario of sample setting, following setting will be applied to VRRP-LB2.
Interface to set |
Interface 1/1 |
Virtual IP Address |
192.168.1.20 |
VRID | 30 |
Setting in the Load Balancer (VRRP-LB2) Management Portal
Setting Items |
Setting value |
Virtual Router ID | 30 |
Priority | 100 |
Tracking | NONE |
Preemption | Check mark |
Track Interface Priority | 0 |
Interfaces bound to this vrid | Check mark |
Setting Items |
Setting value |
IP Address | 192.168.1.20 |
Netmask | 255.255.255.0 |
IP Type | Virtual IP |
Virtual Router ID | 30 |
ICMP Response | NONE |
ARP Response | NONE |
Traffic Domain | 10 (10 is mandatory) |
State | Check mark |
ARP | Check mark |
ICMP | Check mark |
Virtual Server | Check mark |
Enable Management Access control to support the below listed applications | Check mark |
SNMP | Check mark |
Checking VRRP switching¶
Checking Load Balancer (VRRP-LB1) Setting
Checking Load Balancer (VRRP-LB2) Setting
Verification Result of Operations at the Time of Failure¶
**Operation Check at the Time of Load Balancer (VRRP-LB1) Failure
Note
If the VRRP status will not change, click the [ Update ] button in the upper area of the screen.
Note
If the VRRP status will not change, click the [ Update ] button in the upper area of the screen.