VIP Setup

This page assumes that the cluster has been installed and that the failover permissions have been given (see Cluster and Failover Setup) and covers creating a Virtual IP (VIP).

CIDR

While an Interface IP is being added, the CIDR (the subnet mask) must be entered correctly. While a VIP is being added, on the other hand, a CIDR does not need to be entered.

The cluster note

Since the cluster is installed, the TR7 settings are made only on the first device; the cluster synchronizes these settings to the second device automatically. Only the Azure portal operations (adding a NIC and an Azure IP configuration) are per VM and must be made on both devices.

Creating a VIP

A Virtual IP (VIP) that will stay reachable when a device goes out of service is created. This IP is defined first on Azure and then on TR7. Depending on the interface on which the VIP will live, there are two cases; the case that fits the design is followed:

• Case A. The VIP is on an interface that is already in use (for example the management interface). That interface already has an Interface IP (the management IP), it is not added again.
• Case B. The VIP is on a different interface that has not been installed yet. That interface does not have an Interface IP yet; it needs to be added first.

Case A: A VIP on an Interface That Is in Use

If the VIP will be on an interface that is already in use (for example on the management interface), this case is followed. The Interface IPs of the interface already exist; on the management interface these are the management IPs of the two devices. So an Interface IP is not added here; the existing ones are used.

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Step 1 Create the VIP on Azure

(Azure) On the Azure portal the network interface of the first device (Cluster ID 1) is gone to and the IP that will be the VIP is created. It is made sure that the IP is on the same network as that interface.

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Step 2 Add a Public IP (optional)

(Azure) If the VIP will be reachable over the internet, a Public IP is added to the same IP configuration.

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Step 3 Set the VIP communication

(TR7, the first device) In order for the VIP to be able to be carried to the second device, VRRP is enabled. On the Network → Interfaces screen the interface is right clicked and Edit Interface is selected. In the VIP communication field the existing Interface IPs (the management IPs) of the two devices are entered and it is saved.

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Step 4 Add the VIP

(TR7, the first device) The same interface is right clicked, Add IP is selected, the IP type field is made VIP, the VIP address created on Azure in the first step is entered and it is saved. The VIP has been configured on the first device; during a failover TR7 carries this IP to the second device automatically.

INFO

After VIP communication has been set once on an interface, as many VIPs as are wanted can be added to that interface.

Case B: A VIP on a Different Interface

If the VIP will live on a different interface that has not been installed yet (on a new NIC on a different network), this case is followed. This interface does not have an Interface IP yet; first the interface is brought up and an Interface IP is added, and then the VIP is created. Bringing the interface up is the same as the flow on the Network and Interfaces Setup page. (The cluster note above is valid: the Azure operations on both devices, the TR7 settings only on the first device.)

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Step 1 Add the new NICs

(Azure, both devices) On both devices the VM is stopped (deallocated) and a new network interface (NIC) is added for the network of the VIP. The new NIC must be in the same subnet on both devices. While the NIC is being created, Azure assigns an IP automatically (it can also be made static if it is wanted); this IP becomes the Interface IP of the interface. Then the VMs are started again; the new interface appears automatically in TR7 under Network → Interfaces.

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Step 2 Determine the Interface IPs

(Azure, both devices) The IP that Azure creates together with every NIC is the Interface IP of that interface; every device has its own IP. The ones that will be used for VRRP are these Interface IPs. A separate IP for the VIP is added to the NIC of the first device in a later step.

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Step 3 Match the interface with the MAC

(TR7, the first device) The new interface is recognized with its MAC: the MAC of the NIC is read on Azure (Settings → Properties) and is matched in TR7 (Network → Interfaces) by left clicking on the interface.

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Step 4 Create a route table

(TR7, the first device) A new route table is created for the new interface with Add on the Network → Route Tables screen.

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Step 5 Assign the route table

(TR7, the first device) On the Network → Interfaces screen the new interface is right clicked, Edit Interface is selected, the route table created is selected in the Route table field and it is saved.

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Step 6 Add the Interface IPs

(TR7, the first device) An Interface IP is added: the interface is right clicked, Add IP is selected, the IP type field is made Interface IP, the IPs of the two devices determined in step 2 are added with the correct CIDR (the subnet mask) and it is saved. These Interface IPs will be used for VRRP.

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Step 7 Create the VIP on Azure

(Azure, the first device) On Azure the IP that will be the VIP is created on the new interface of the first device (on the same network). (Optional) A Public IP is added to the same IP configuration.

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Step 8 Set the VIP communication

(TR7, the first device) VRRP is enabled: the interface is right clicked, Edit Interface is selected, the two Interface IPs added in step 6 are entered in the VIP communication field and it is saved.

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Step 9 Add the VIP

(TR7, the first device) The VIP is added: the interface is right clicked, Add IP is selected, the IP type field is made VIP, the VIP created on Azure is entered and it is saved.

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Step 10 Set the default gateway

(TR7, the first device) Last, only after the interface has taken its Interface IP, the default gateway is set in the route table: the pencil (editing) icon is clicked on the Network → Route Tables screen and the default gateway is entered. The reason why this step is made at the very end is that TR7 checks that the interface IPs and the gateway are on the same network.

INFO

The Azure default gateway

In every Azure subnet the default gateway is the first host address of the subnet: the network address + 1 (.1). For example, for the 10.1.0.0/24 subnet the gateway is 10.1.0.1. (Azure reserves the first four and the last address of every subnet; .1 is always the gateway and cannot be changed.)

After the VIP is created, it is made sure that the failover permissions have been given so that TR7 can carry the VIP automatically during a failover (see Cluster and Failover Setup).

INFO

In a failover the VIP is carried over the Azure (ARM) API; for this reason the transition, unlike the instantaneous transition in the classic networks, can take between a few seconds and half a minute.