Solved

160GB DAT only has 80GB capacity

Posted on 2012-03-12
3
472 Views
Last Modified: 2012-03-13
Hi,
Using Symatec Backup Exec 11d.  New 160GB backup drive is only providing a capacity of 80GB - I gather this has something to do with compression but I'm uncertain how to get the stated 160GB capacity.  Any assistance appreciated.  Thanks.
0
Comment
Question by:t38
3 Comments
 
LVL 39

Accepted Solution

by:
Adam Brown earned 250 total points
ID: 37711110
A lot of tape manufacturers advertise their capacity in maximums based on a 100% compression rate. Most 160GB DAT cartridges are actually 80/160, which means 80GB uncompressed, 160GB with 100% compression. So you're probably stuck with 80 unless you turn on compression for your backups.
0
 
LVL 25

Assisted Solution

by:Fred Marshall
Fred Marshall earned 250 total points
ID: 37711597
The important thing is the compression ratio.  No tape manufacturer can tell you what it will be because it's not only dependent on the compression method chosen AND your actual data.  Some data is highly compressible and some is not.  So if a tape will hold 80GB and if there is allusion to 160GB, that must refer to an average compression ratio of 2:1 ... or a data size ratio of 1:2 depending on how you like to say it.

You can take a program like 7Zip which has pretty good compression algorithms available and compress some of your files just to see what happens.
0
 

Author Closing Comment

by:t38
ID: 37713765
That clarifies things, thanks to you both for your input
0

Featured Post

Best Practices: Disaster Recovery Testing

Besides backup, any IT division should have a disaster recovery plan. You will find a few tips below relating to the development of such a plan and to what issues one should pay special attention in the course of backup planning.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

This article lists the top 5 free OST to PST Converter Tools. These tools save a lot of time for users when they want to convert OST to PST after their exchange server is no longer available or some other critical issue with exchange server or impor…
This article aims to explain the working of CircularLogArchiver. This tool was designed to solve the buildup of log file in cases where systems do not support circular logging or where circular logging is not enabled
To add imagery to an HTML email signature, you have two options available to you. You can either add a logo/image by embedding it directly into the signature or hosting it externally and linking to it. The vast majority of email clients display l…
This video shows how to quickly and easily add an email signature for all users on Exchange 2016. The resulting signature is applied on a server level by Exchange Online. The email signature template has been downloaded from: www.mail-signatures…

770 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question