In this video, you'll learn about data center storage. So what's going on in the data center?
Well, in the data center, you have centralized storage. And the idea is that your servers
are not keeping their files locally, but you keep them on the centralized storage and that
makes it easy to protect your storage to make backups, and so on. Fiber Channel and iSCSI
are common storage solutions used in the data center. And in both, a dedicated storage network
is used to connect servers to your storage. iSCSI in Linux environments is fairly popular
because in iSCSI, SCSI packets are sent over an IP network. So instead of using the SCSI
protocol to talk to your SCSI hard disk, you put a network between the hard disks and your servers.
The nice thing about iSCSI is that iSCSI services can easily be offered by
Linux servers. Most Linux servers are offering the iSCSI target, and this iSCSI target is what
you install to expose drives to externally. So you could convert a Linux server with a proper
configuration in a data center storage area network, if you want. So on the server, you need
the iSCSI target, and on the client, you use a component known as the iSCSI initiator, which
will reach out and find the drives provided by the iSCSI storage device. Fiber Channel is also
commonly used, but Fiber Channel is not as open as iSCSI. The protocols depend on the vendor of
the hardware. Now let's find out what needs to be done to connect your servers to data center storage.
While doing so, very frequently redundant network connections are used, because you are
connecting to an external drive. And what is going to happen if your network cable fails?
Well, that is exactly what you don't want to happen, and that is why redundant network connections
are coming in. But if you have redundant network connections, the problem would be that the same
hard disk would be seen twice. So you don't see one, but you would see two hard disks, or even four
hard disks, depending on the configuration of your storage. And that is why, in order to implement
redundant networking, multipathing is commonly used. And that makes that you don't see the same
device twice, but a multipath driver provides one unified storage device that is used. And you just
use the multipath driver, and the multipath driver will make sure that the appropriate network
connection is used. And if one connection is going down, no problem for that driver,
you will still keep on being connected to your storage.