i want to build a server for a large website but have a technical question. how are all the raid arrays on each rackmount connected? are all the drives connected to an ethernet cable and to a router and then to the server or are all the raid arrays connected by external sas or sata cables? what about a tape drive connection? i want a system that will allow me to use raid 10 and have lots of add on capabilities since i will most likely need more storage in the future for when the website users grow.
You can use iSCSI or AOE to mount the disks over ethernet if you want, or you can use eSATA, or fiber channel. Or, you can simply throw up cheap little NFS servers on the network and export their filesystems to the main servers. Or you can look at distributed systems like Tahoe-LAFS.
The possibilities are endless.
Whatever you do, talk to a managed services provider who has 'been there, done that'.