Unitt Zero Data Loss Service (ZDLS) The ultimate weapon against data loss

Transcription

1 Zero Data Loss Service (ZDLS) The ultimate weapon against data loss

2 The ultimate protection for your business-critical data In the past, ultimate data protection was a costly issue, if not an impossible one. Enterprise solutions like Metroluster are only accessible to large enterprises or multinationals because of their high cost. That s a pity, because the demand for this type of application grows every day. Unitt makes Metroluster technology available to all through the Zero Data Loss Service (ZDLS). In this white paper, we will discuss how that works and introduce the NetApp s Metroluster solution as well as Unitt s ZDLS (Zero Data Loss Service) service that is based on it. 2

3 First of all, determine how important the availability of your data is Data indeed play an important role in company processes. Your application data are your most precious asset and the cost of data loss can be very high. It is therefore crucial to ponder the question of what happens with your data in case of problems with your data centre. Perform a risk analysis of what can go wrong and what the (financial) consequences are for your company. The answer to this thinking exercise can be expressed through the RPO (recovery point objective) with which you determine the maximum amount of time preceding a system failure for which you can afford to lose data without endangering the continuity of your business. In many companies, absolutely none of the data are expendable: the RPO is then 0. A solution to attain that level of certainty is synchronous replication of your storage over several locations. 3

4 Synchronous or asynchronous replication? 4 If you want to lose as little data as possible during a failure, you have to replicate your data. For instance, if you have a web environment that processes customer transactions and saves those data onto its storage system (like e.g. a SAN or storage area network or a NAS or network attached storage), those same data are also simultaneously saved in another data centre. In case of a failure in the first data centre, the data will still be available in the second data centre. Replication can happen in two ways and this determines the RPO. With synchronous replication, saving a data set is only confirmed to the application (like e.g. a web server) when the set has been saved successfully in both data centres. This can slow down the application, because the network connection between both data centres induces a supplementary delay and the application will wait until it has received the confirmation of successful saving. Data loss is however excluded: the RPO is 0 and you are certain that exactly the same data are present in both locations. Another method is asynchronous replication. Here, the application receives a confirmation as soon as saving a data set to the first data centre has succeeded. If, in the meantime, a failure occurs in the first data centre, the data set may not have reached the second data centre yet and you are then at risk of suffering data loss. The RPO in this case is typically 15 minutes or more. In this scenario, the application runs faster because no supplementary delay is introduced. The delay that is introduced by synchronous replication can be kept to a minimum by placing both data centres close enough to each other. That is why, for this configuration, Unitt uses two data centres that are located less than 10 km apart. This still guarantees enough speed in your applications that replicate synchronously (all writing commands reach both SANs in a few milliseconds), while the distance is sufficiently long to avoid a local disaster could impact both data centres.

5 NetApp Metroluster: the ultimate weapon against data loss One of the products that offer synchronous replication of data is Metroluster from storage provider NetApp. This solution combines NAS and SAN technologies to synchronous replication to make your data available continuously and avoid data loss. Metroluster offers the following benefits: ontinuous availability One single system Proven technology The Metroluster software expands NetApp filers to an arraybased active-active storage cluster. This way, you don t have to reboot servers, restart applications or run failover scripts when your storage system fails in one of both data centres. In that event, the application isn t influenced by the failure because storage has been active all the time in the second data centre. So, there is a transparent recovery from a failure. Many replication solutions require that you manage, configure and maintain both SANs separately in both locations. That is somewhat sensitive to mistakes, because inconsistencies between the configurations may lead to errors that are hard to fathom. Metroluster, however, is a truly clustered storage solution, where both SANs are managed as one single entity. In other words, the administrative overhead decreases, as does the risk of human error. NetApp Metroluster has been tested in combination with virtualisation and clustering technologies from VMware, Microsoft, Symantec, IBM and many others. Thanks to these partnerships of NetApp, Metroluster can be integrated flawlessly in your IT environment. 5

6 The Metroluster solution applied in practice Metroluster is an efficient data protection system in many different scenarios. Here are a few examples: 1. A redundant VMware environment 6 In both data centres, you have virtual machines running in a VMware vsphere environment. If a problem occurs with a virtual server in one of the data centres, VMware will keep on running the virtual machine in a high availability setup in the other data centre. You replicate the data with Datacenter 1 Metroluster. If something goes wrong with one of both SANs, no manual intervention is required in the vsphere environment: the IP address of the data automatically points to the SAN that is still in working order. Datacenter 2 Firewall node1 Firewall node2 ESX node 1 ESX node 2 ESX node 3 ESX node 4 ESX node 5 ESX node 6 M Metroluster node1 Metroluster Metroluster node2

7 7 2. A cluster of database servers Imagine you have a Microsoft SQL Server running of which you want to guarantee availability. You then run a database cluster of which the nodes are each located in their own data centre. The database servers share the same IP address, which is used by the clients. If one of both data centres fails, the clients can reach the server that is still in working order via that IP address. By replicating the storage with Metroluster, you can use the standard edition of SQL Server instead of the Enterprise edition. The SQL Server indeed doesn t need to know about the data replication: if one SAN fails, the IP address of the Metroluster will automatically refer to the other SAN, in complete transparency with respect to the database server. Datacenter 1 Datacenter 2 Firewall node1 Firewall node2 D node 1 node 2 node 3 node 4 node 5 node 6 Geo-distributie Firewall node1 Firewall node2 Database node1 Database node2 M Metroluster node1 Metroluster Metroluster node2

8 8 3. NFS or IFS shares without data loss By putting a NetApp filer in every data centre and replicating it with Metroluster, you can share files without risk of data loss. In this case, you let the NetApp filers share your files via NFS (for Linux/ Unix) or IFS (for Windows) in order to make them, for instance, accessible to your web servers. If one of both SANs fails, your files will transparently stay shared by the other SAN and no data are lost. Datacenter 1 Datacenter 2 Loadbalancer node 1 Loadbalancer node 2 Application server 1 (A) Application server 2 (P) M Metroluster node1 Metroluster Metroluster node2

9 9 Zero Data Loss Service (ZDLS) as a cost-efficient alternative Even though Metroluster is a cost-effective solution in comparison with other solutions for storage replication, the investment in the necessary infrastructure remains too important for many companies. That is why Unitt offers the technology asa-service under the name ZDLS (Zero Data Loss Service): without any investment from your end, you gain access to Metroluster technology for your storage, for a fixed monthly fee, including service and management, with SLAs up to four nines (a guaranteed resolution time of under 4,5 minutes). Unitt sets up all the layers of the solution redundantly and distributes systems and data over two top-notch data centres (Tier III+). There is optical fibre between both data centres, along two different pathways over which runs 10 Gbit of Ethernet traffic. The SANs in both data centres save the data to each other in real time, so both data sets remain identical even if one data centre fails completely. ZDLS offers you the following benefits: Flexibility You don t need to invest in infrastructure and you will thus never lack storage or pay for too much storage. When your needs for data capacity grow, you simply expand your storage on our service. In an OPEX model, you only pay for the capacity you truly use. Quick entry You can quickly enter into an advanced, proven technology with state-of-the-art components. You no longer need to invest time in setting up an infrastructure and managing it, but you can immediately entrust your data to Metroluster. In the Benelux Unitt offers you the guarantee that your data remain within national borders. Unlike other hosting service providers, we thus cannot be subject to an enforcement order from the American government to provide access to your data. Partnership with NetApp Unitt has developed a close partnership with NetApp, which allows us to gain access to the storage supplier s best engineers. We can thus provide you with optimum support. ZDLS is available in two forms: Fully shared environment You pay on a monthly basis, per batch of 25 GB of synchronously replicated storage. Your storage is located in an environment that is also used by other clients, which helps minimise costs. Unitt manages and monitors the hardware and always has enough storage space in case of unexpected growth. Dedicated shelves This is the model you choose for very demanding applications. By using one or several personal shelves, you reserve the full Input/ Output of the storage disks entirely for your own organisation.

10 Full redundancy thanks to the multi-data centre setup in ZDLS With ZDLS, you can build a multi-data centre setup in a costefficient manner with LANs in the two data centres that operate as one single logical network. Unitt achieves this with a redundant optical fibre connection and also connects the data centres to the Internet in a fully redundant fashion. For this, we use BGP (Border Gateway Protocol), with which failure of an uplink is automatically compensated by the remaining connections. A multi-data centre setup enhances the availability of your applications and data. So if you choose our ZDLS solution, your data will also be protected in a cost-efficient manner. In case of failure in one of both data centres, you don t lose any data. Both data centres are connected by a layer 2 network, so both SANs form one local Metroluster. The redundant server and network infrastructure above it uses your storage as if it was one single SAN. 10 onclusion: zero downtime is within reach If you wish to avoid any risk of data loss, Unitt s ZDLS is the answer. This solution based on Metroluster is accessible to all and is thus more than a cost-efficient alternative. It all starts with the most important question: how much data loss or downtime can your business afford?

11 About Unitt Unitt provides high-end hosting solutions to satisfy the requirements of demanding business users. We develop and manage complex business hosting services using our in-depth knowledge of the latest technologies. Unitt was founded by ombell. Unitt provides 24/7 support in your own language, direct contact with engineers who manage your infrastructure, as well as rock-solid guarantees on service levels. The services, which include dedicated server environments and public and private cloud environments, rely on high-tech components. About NetApp NetApp creates innovative storage and data management solutions that deliver outstanding cost efficiency and accelerate business breakthroughs. UNITT achieved Platinum status in NetApp s Partner Program for Service Providers. Thanks to this, customers of both UNITT and NetApp can get the most out of all the features that NetApp s technology has to offer and the services that UNITT adds as a service provider that is also a partner of NetApp. 11

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