""Aaron Ajello"" wrote in message news:200211050047.AAA01492@;groupstudy.com... > I manage an EMC Clariion, which is their middle range SAN. The advantage to > is you can add disk space to an existing server quickly and easily, > sometimes without a reboot if it's already connected to the SAN. You can > also easily move a volume from one server to another. Another use is > something they call snap. Snapping is taking a volume and creating a > second, virtual copy that you can allow another server to see. Say you had > a database you wanted to test something out on, you could snap it and then > allow another, test server to see the snap copy. Then you test what ever > you want without actually affecting the original, production data. Another > advantage is better use of disk space. You could create a RAID 5 and then > chop it up into 4 volumes and give one volume to four different servers, or > you could give them all to one server, or whatever else. You do have to > worry about contention, but it's possible to take better advantage of disk > space.
Aaron, I have some questions you might be able to answer. Is this an example of what you call snapping? http://www.samag.com/documents/s=1824/sam0201j/0201j.htm If so, what's the difference between doing snapping with software (e.g. Solaris default or Veritas) and with a storage area network? Are snaps the same thing as a scratch disk? I guess my question is: what's a scratch disk? Why would you want a regular disk (not in a RAID 0, 1, 0+1, 5), or set of disks, in a volume besides 'snaps'? Also I find RAID 0, 0+1, and 5 and volumes interesting because you can theoretically use up the closest spindles on the disk (which I understand to be faster for disk I/O) for certain purposes. Is there any practice/theory behind doing this? Is it more of an art or a science? Where does one learn how to do volume sizing for growth/performance, or does the SAN do it for you automagically in some ways? How does this `better advantage of disk space' work, exactly? What do networks have to do with this? Thanks, -dre Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=56863&t=56857 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
