What is RAID in servers? What are RAID 0, 1, 2, 3, 4, 5 Differences between 0 1 2 3 4 5? I searched but i could not figure out this exactly. Explain this..
What will happen if Raid is not availabe? To use RAID 1 should i buy another harddisk in my server..Assume if i have one 80 GB Hard disk alone in my server without Raid facility?
It sounds like you are planning to host websites on a server at home. Unless you are only hosting a personal homepage I would strongly advise against it, there are several reasons why its a bad idea.
No ...I dont have that idea..I am going to buy from one server hosting company...Just want to know about RAID ... Ok..Answer this please What will happen if Raid is not availabe? To use RAID 1 should i buy another harddisk in my server..Assume if i have one 80 GB Hard disk alone in my server without Raid facility?
Yes, you will need an additional drive if you want Raid 1. In Raid 5 you will need 3 drives minimum. Raid 1 is a level of redundancy that will allow your site to continue operating if a drive were to go down, that is why there are 2 drives. Another way I like to put it is that it allows you to rest easy at night, instead of worrying about if you site is up. As far as your example with an 80 gig drive, if you did raid 1, you would have 2 x 80, however you would only see 1 x 80 in your back end b/c of the raid array. Hope that helps.
You must have a hardware or software RAID controller for RAID to work. You host will need to set this up when they build the server. It's not easy and most times not possible to migrate an existing server to RAID. I can't recommend using a server without at least a RAID 1 array, RAID 5 is preferable, RAID 10 if it is a database or you need better disk performance. This is a great RAID comparison chart: http://www.pcguide.com/ref/hdd/perf/raid/levels/comp-c.html