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In this video, you'll learn about data center storage. So what's going on in the data center?

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Well, in the data center, you have centralized storage. And the idea is that your servers

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are not keeping their files locally, but you keep them on the centralized storage and that

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makes it easy to protect your storage to make backups, and so on. Fiber Channel and iSCSI

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are common storage solutions used in the data center. And in both, a dedicated storage network

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is used to connect servers to your storage. iSCSI in Linux environments is fairly popular

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because in iSCSI, SCSI packets are sent over an IP network. So instead of using the SCSI

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protocol to talk to your SCSI hard disk, you put a network between the hard disks and your servers.

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The nice thing about iSCSI is that iSCSI services can easily be offered by

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Linux servers. Most Linux servers are offering the iSCSI target, and this iSCSI target is what

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you install to expose drives to externally. So you could convert a Linux server with a proper

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configuration in a data center storage area network, if you want. So on the server, you need

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the iSCSI target, and on the client, you use a component known as the iSCSI initiator, which

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will reach out and find the drives provided by the iSCSI storage device. Fiber Channel is also

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commonly used, but Fiber Channel is not as open as iSCSI. The protocols depend on the vendor of

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the hardware. Now let's find out what needs to be done to connect your servers to data center storage.

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While doing so, very frequently redundant network connections are used, because you are

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connecting to an external drive. And what is going to happen if your network cable fails?

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Well, that is exactly what you don't want to happen, and that is why redundant network connections

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are coming in. But if you have redundant network connections, the problem would be that the same

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hard disk would be seen twice. So you don't see one, but you would see two hard disks, or even four

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hard disks, depending on the configuration of your storage. And that is why, in order to implement

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redundant networking, multipathing is commonly used. And that makes that you don't see the same

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device twice, but a multipath driver provides one unified storage device that is used. And you just

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use the multipath driver, and the multipath driver will make sure that the appropriate network

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connection is used. And if one connection is going down, no problem for that driver,

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you will still keep on being connected to your storage.