Data Center Interconnect (DCI) is a network solution that realizes interconnection between multiple data centers. Data centers are important infrastructure for digital transformation. With the rise of cloud computing, big data, and artificial intelligence, enterprise data centers are increasingly used. To meet the needs of scenarios such as cross-regional operation, user access, and remote disaster recovery, more and more organizations and enterprises deploy multiple data centers in different regions. At this time, multiple data centers need to be interconnected.
Was ist ein Rechenzentrum?
With the continuous development of industrial digital transformation, data has become a key production factor, and data centers are responsible for the calculation, storage and forwarding of data, and are the most critical digital infrastructure in the new infrastructure. A modern data center mainly includes the following core components:
Computersysteme, einschließlich allgemeiner Computermodule zum Bereitstellen von Diensten und -Hochleistungs-Computermodulen, die Super-Rechenleistung bieten.
Speichersystem, einschließlich Massenspeichermodulen, Datenmanagement-Engine, speicherdediziertem Netzwerk usw.
Energy system, including power supply module, temperature control module, IT management module, etc.
The data center network is responsible for connecting general computing, high-performance computing and storage modules within the data center, and all data interactions between them must be realized through the data center network.
Among them, the general computing module directly undertakes the user's business, and the physical basic unit it relies on is a large number of servers. If the server is the body of the data center, then the data center network is the soul of the data center.
Warum brauchen wir Rechenzentrumsverbindungen?
At present, the construction of data centers for various organizations and enterprises is very common, but it is difficult for a single data center to meet the business needs of the new era, and there is an urgent need for interconnection of multiple data centers. Mainly reflected in the following aspects.
Schnelles Wachstum der Unternehmensgröße
At present, emerging businesses such as cloud computing and intelligence are developing rapidly, and the number of related applications is also increasing rapidly, and these applications are strongly dependent on data centers. Therefore, the scale of business undertaken by data centers is growing rapidly, and the resources of a single data center will soon be insufficient. Due to factors such as data center construction and energy supply, it is impossible for a single data center to expand indefinitely. When the business scale grows to a certain extent, it is necessary to build multiple data centers in the same city or in different places. At this time, multiple data centers need to be interconnected and cooperate to complete business support.
In addition, in the context of economic digital transformation, in order to achieve common business success, companies in the same industry and in different industries need to frequently share and cooperate at the data level, which also requires interconnection between data centers of different companies. Intercommunication.
Überregionaler Nutzerzugriff- wird immer häufiger
In recent years, the business of data centers has changed from centered on Web services to centered on cloud services and data services, and the scope of users of related organizations and enterprises is no longer limited by regions. Especially when the mobile Internet is very popular, users expect to enjoy high-quality services anytime, anywhere. In order to meet the above demands and further improve the user experience, qualified enterprises usually build multiple data centers in different regions, so as to facilitate the nearby access of users across regions. This requires that business deployment can cross data centers and supports interconnection of multiple data centers.
Strenge Anforderungen für Offsite-Backups und Disaster Recovery
Nowadays, people's daily work is more and more dependent on various application systems, and the continuity of these application systems depends on the stable operation of the data center system. At the same time, more and more attention is paid to data security, business reliability and continuity, and backup and disaster recovery have become rigid requirements. The real environment is an environment full of uncertainty and various risks. Data centers are always facing potential threats such as various natural disasters, man-made attacks, and accidental accidents. By deploying multiple data centers in different places to improve business continuity and robustness As well as the high reliability and availability of data, it has gradually become an effective solution generally recognized by the industry. To deploy backup and disaster recovery solutions between different data centers, you must first complete the interconnection of data centers.
Trends in Rechenzentrumsvirtualisierung und Ressourcenpooling
With the gradual maturity of the cloud computing business model, various applications and traditional IT services are "going to the cloud", and cloud business is becoming a new value center. Therefore, the transition from traditional data centers to cloud-based data centers has become a mainstream trend. Virtualization and resource pooling are the key features of cloud-based data centers. The core idea is to transform the smallest functional unit of a data center from a physical host into a virtual machine (Virtual Machine). These VMs have nothing to do with the physical location, the resource usage can be flexibly scaled, and they support free migration across servers and data centers, thereby realizing resource integration within and across data centers, forming a unified resource pool, and greatly improving the flexibility of resource utilization. performance and efficiency. The interconnection between data centers is a prerequisite for realizing VM migration across data centers. Therefore, data center interconnection is also an important link in realizing data center virtualization and resource pooling.
Welche Optionen gibt es für die Rechenzentrumsvernetzung?
In order to better meet the needs of cloud-based data centers, many data center network solutions have emerged, such as Huawei data center switches (CloudEngine series), Huawei data center controllers (iMaster NCE-Fabric), and intelligent network analysis platforms (iMaster NCE-FabricInsight), provides the following two recommended data center interconnection solutions.
End-to--VXLAN-Lösung
Data center interconnection based on end-to-end VXLAN tunnels means that the computing and network of multiple data centers are unified resource pools, which are centrally managed by a cloud platform and a set of iMaster NCE-Fabric, and multiple data centers are unified The user's VPC (Virtual Private Cloud, virtual private cloud) and subnets can be deployed across data centers to directly realize business interoperability. The deployment architecture is shown in the following figure.
In this solution, end-to-end VXLAN tunnels need to be established between multiple data centers. As shown in the figure below, firstly, the Underlay routes between the data centers are required to communicate with each other; secondly, at the overlay network level, EVPN must be deployed between the Leaf devices of the two data centers. In this way, the Leaf devices at both ends discover each other through the EVPN protocol, and transmit VXLAN encapsulation information to each other through the EVPN route, thereby triggering the establishment of an end-to-end VXLAN tunnel.
This solution is mainly used to match Muti-PoD scenarios. PoD (Point of Delivery) refers to a set of relatively independent physical resources. Multi-PoD refers to using a set of iMaster NCE-Fabric to manage multiple PoDs, and multiple PoDs form an end-to-end VXLAN domain. This scenario is suitable for the interconnection of multiple small-scale data centers that are close to each other in the same city.
Segment VXLAN-Lösung
The data center interconnection based on Segment VXLAN tunnel means: in the multi-data center scenario, the computing and network of each data center are independent resource pools, which are independently managed by their respective cloud platforms and iMaster NCE-Fabric. The center is an independent VXLAN domain, and another DCI VXLAN domain needs to be established between the data centers to achieve interoperability. Moreover, users' VPCs and subnets are deployed in their own data centers. Therefore, the business interoperability between different data centers needs to be orchestrated by a higher-level cloud management platform.
In this solution, VXLAN tunnels must be established within and between data centers. As shown in the figure below, firstly, underlay routes between data centers are required to communicate with each other; secondly, at the overlay network level, EVPN must be deployed between Leaf devices in the data center and DCI gateways, as well as between DCI gateways in different data centers. In this way, related devices discover each other through the EVPN protocol, and transmit VXLAN encapsulation information to each other through EVPN routes, thereby triggering the establishment of Segment VXLAN tunnels.
This solution is mainly used to match the Multi-Site scenario, which is suitable for the interconnection of multiple data centers located in different regions, or the interconnection of multiple data centers that are too far away to be managed by the same set of iMaster NCE-Fabric.
Welche Schlüsseltechnologien sind für die Rechenzentrumsvernetzung erforderlich?
In essence, VXLAN is a tunneling technology. It can superimpose a Layer 2 virtual network on any network reachable by route, and realize the intercommunication within the VXLAN network through the VXLAN gateway, and at the same time, it can also realize the intercommunication with the traditional non-VXLAN network. VXLAN uses MAC in UDP encapsulation technology to extend the Layer 2 network, encapsulates Ethernet packets on top of IP packets, and transmits them in the network through IP routing. The intermediate device does not need to pay attention to the MAC address of the VM; and the IP routing network has no network structure restrictions , with large-scale scalability, so that VM migration is not limited by the network architecture. For more information on VXLAN technology, see "In-depth: What is VxLAN?".
EVPN is a next-generation full-service bearer VPN solution. EVPN unifies the control plane of various VPN services, and uses the BGP extension protocol to transmit the reachability information of Layer 2 or Layer 3, realizing the separation of the forwarding plane and the control plane. With the in-depth development of data center networks, EVPN and VXLAN have been gradually integrated. VXLAN introduces the EVPN protocol as the control plane, which makes up for the lack of VXLAN without a control plane at first; EVPN uses VXLAN as the public network tunnel, which makes EVPN more widely used in scenarios such as data center interconnection.