Vro configured in Server Load balancer Mode

Vro configured in Server Load balancer Mode
The Master router virtual MAC Address Allocation Function described above enables different hosts to send traffic to different routers in the backup group. However, to enable the router in the backup group to forward the traffic sent by the host, you also need to create a virtual forwarder on the router. Each virtual forwarder corresponds to a virtual MAC address in the backup group and forwards traffic from the destination MAC address to the virtual MAC address. 1. the creation process of a virtual forwarder is as follows: (1) After the vro in the backup group obtains the virtual MAC address assigned to it by the Master router, it creates the virtual forwarder corresponding to the MAC address, this vrovf is called the VF Owner (VirtualForwarder Owner, Owner of the virtual forwarder) corresponding to the virtual MAC address ). (2) The router advertises the information of the virtual forwarder to other routers in the backup group. (3) After receiving the virtual Forwarder Information sent by the vro, other vrouters in the backup group will create a local virtual forwarder corresponding to the virtual MAC address. As can be seen from www.2cto.com, The vro in the backup group not only needs to create a virtual forwarder corresponding to the virtual MAC address assigned by the Master router for it, but also needs to create a virtual forwarder corresponding to the virtual MAC address advertised by other routers.
2. The weight and priority of the virtual forwarder indicate the forwarding capability of the router. The higher the weight, the stronger the forwarding capability of the router. When the weight is less than a certain value, the router cannot forward traffic to the host. The priority of the virtual forwarder is used to determine the status of the virtual forwarder. Among the virtual forwarder corresponding to the same virtual MAC address on different routers, the highest priority virtual forwarder is Active, it is called AVF (Active Virtual Forwarder) and is responsible for forwarding traffic. Other Virtual senders are in the Listening status, known as LVF (Listening Virtual Forwarder) and listen to the AVF status. The priority value range of the virtual forwarder is 0 ~ 255, where 255 is reserved for the VF Owner. If the weight of the VF Owner is higher than or equal to the lower failure threshold, the priority of the VF Owner is 255. The rules for a device to calculate the priority of a virtual forwarder based on the weight of the virtual forwarder are as follows: if the weight is higher than or equal to the lower failure threshold and the device is VF Owner, the priority of the virtual forwarder is up to 255. If the weight is higher than or equal to the lower failure threshold and the device is not the VF Owner, the priority of the virtual forwarder is weight/(number of local AVF + 1 ). If the weight is lower than the lower failure threshold, the priority of the virtual forwarder is 0. 3. A backup relationship is formed between multiple vbrs corresponding to the same virtual MAC address on different routers in the backup group. In the example 4-9, the information of the virtual forwarder on each vro in the backup group and its backup relationship are described. Figure: In Server Load balancer mode, the virtual MAC addresses assigned by the Master Router A to itself, Router B, and Router C are 000fe2ff0011, 000fe2ff0012, and 000fe2ff0013 respectively. VF1, VF 2, and VF 3 are corresponding to the virtual MAC address. You have created these three virtual Referer on Router A, Router B, and Router C to form A backup relationship. For example, VF 1 on Router A, Router B, and Router C backs up each other. The VF Owner of Router A is VF 1, and the VIP priority of VF 1 on Router A is 255. Therefore, as AVF, VF 1 on Router A forwards traffic destined for A virtual MAC address 000fe2ff0011. The virtual forwarder priority of VF 1 on Router B and Router C is: weight 255/(number of local AVF + 1) = 127, lower than the priority of VF 1 on Router. Therefore, VF 1 on Router B and Router C is used as LVF to monitor the status of VF 1 on Router. When VF 1 on Router A fails, select the LVF with the highest priority from VF 1 on Router B and Router C as AVF, forwards traffic destined for a virtual MAC address 000fe2ff0011.
[Note] the virtual forwarder always works in the preemption mode. For LVF and AVF backed up by each other on different routers, if the virtual forwarder priority of LVF received by AVF is lower than the local virtual forwarder priority, LVF will be preemptible to AVF. 4. When the AVF of the VM forwarder fails, the new AVF that takes over the VM will create the Redirect Timer and Timeout Timer timers for the VF. Redirect Timer: VF redirection Timer. Before the timer times out, the Master router uses the virtual MAC address corresponding to the VF to respond to the host's ARP/ND request. After the timer times out, the Master router no longer uses the virtual MAC address corresponding to the VF to respond to the host's ARP/ND request. If the VF Owner recovers before Redirect Timer times out, the VF Owner can quickly participate in traffic load balancing. Timeout Timer: VF survival Timer, that is, the duration for AVF to take over the VF Owner. Before the timer times out, the VF is retained on the vrouters in the backup group. AVF forwards packets whose destination MAC address is the vmac address of the VF. After the timer times out, the vro in the backup group deletes the VF and no longer forwards packets whose destination MAC address is the vmac address of the VF. Www.2cto.com
5. the virtual repeater's monitoring function AVF is responsible for forwarding the traffic destined for the MAC address of the virtual forwarder. When the upstream link of the AVF connection fails, if LVF cannot be notified to take over in time, the host that uses the MAC address of the gateway as the MAC address in the local area network cannot access the external network. The monitoring function of the virtual forwarder can solve the above problems. Use NQA (Network Quality Analyzer, Network Quality analysis) and BFD (Bidirectional Forwarding Detection, Bidirectional Forwarding Detection) to monitor the Uplink Status of AVF connections, the Track function is used to establish a linkage between the virtual forwarder and NQA/BFD. When the uplink fails, the status of the Track item changes to Negative, and the weight of the virtual forwarder reduces the specified amount, so that the vro with a higher priority can be preemptible to AVF to replace the forwarding traffic. The virtual repeater monitoring function can also be used to monitor AVF status through Track on LVF. When AVF fails, the LVF working in the Fast Switching Mode of virtual repeater can quickly become AVF, to ensure that the communication will not be interrupted. This article is from the fat shark network.