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| *停權中*  加入日期: Mar 2012 
					文章: 161
					
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				關於儲存設備容量需求的計算問題
		
	 各位學長: 底下這題是個計算題: An application uses 20, 10 GB devices. A pointer-based full volume replica of the application is required every 6 hours. Each replica will be kept for 24 hours. The data changes by 10% every 4 hours. How many replica devices are required? 我是這樣想的: (10*20/6*24*(1.1)^6)/10=141.724, ---142 可是答案是80。不曉得哪裡錯了,再請學長們指導,萬分感謝!! | |||||||
|  2012-08-13, 11:21 AM
			
			
	#1 |   | 
| Major Member  加入日期: Dec 2005 
					文章: 151
					
				 | A pointer-based full volume replica of the application is required every 6 hours. 重點只在這一句,100%複製。 24/6 * 20=80 打完收工。 | ||
|  2012-08-13, 01:18 PM
			
			
	#2 |   | 
| *停權中*  加入日期: Mar 2012 
					文章: 161
					
				 | 引用: 
 學長真是了不起,豁然開朗,心情愉快!! 能不能再請教一題?感謝!! A department within an organization requires 200 GB of storage for their business application. The production LUN is RAID 1+0 protected and has a local and remote replica. The local replica is on a RAID 1 LUN and the remote replica is on a five-disk RAID 5 LUN. If the cost per GB of storage is $2.00, what is the chargeback cost to the department for application storage? 答案是$2100,完全無法理解>< | |
|  2012-08-13, 02:35 PM
			
			
	#3 |   | 
| Junior Member    加入日期: May 2005 您的住址: Autobahn, Deutschland 
					文章: 743
					
				 | RAID 0+1 -> (100+100)x2 = 400G RAID 1 -> 200x2 = 400G RAID 5 -> 200x5/(5-1) = 250G (400+400+250)x2= 2100 引用: 
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|  2012-08-13, 02:45 PM
			
			
	#4 |   |