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stranger12's avatar
stranger12
11 years ago
Solved

backupexec

Hi All,

 

I am new to backupexec and tapes .

I am having some very slow backup speed using lt03 so have some questions as below and appreicate your help

 

1.with LT03 should I expect 160MB/s as read/write speed as per the specification ?

 

2.with LT03 when it says 400/800GB is that 400GB with 1:1 compression and 800GB with 1:2 ? If so why does sources on internet says backing up with compression enabled is faster as I would have thought it takes more time to compress and then write hence slower speed?

 

3.we are getting around 1000MB to 2000MB max for exchange backup, what is the speed you are seeing on average ?

 

4.is there a way to change MB per minute to second ?

 

5.what is the difference between kernel mode and usermode driver for tape ?

 

6.How can I know if my tape drive has 2 drives so can do two jobs ? the tape drive we have is tl2000 dell and has 2 bunch of 8 slots i think so I would have thought it can do 2 jobs at the same time but it can only do 1 job .

 

many thanks for your help

2010
Backup and Recovery
Backup Exec
Windows Server (2003-2008)
  • pkh's avatar
    pkh
    11 years ago

    1.  This is a theoretical speed, but it is very hard to achieve in real life.  Speed is dependent on a lot of factors, like CPU, RAM, network speed, application speed, etc.  Tape writing speed is only one factor.

    There are some tuning that you can do with BE, including tape drives.  See my article below

    https://www-secure.symantec.com/connect/articles/tuning-backup-exec

    2. You can test out the truth of this claim by backing up the same resource to tape with and without compression.  LTO3 does not have hardware compression so the difference should be apparent.

    3. Everybody's speed would be different.  If I tell you that I get better speed, it would be meaningless in your case because you cannot replicate my environment.

    4. No.

    5. A kernel mode drive as the name implies is part of the kernel.  For more details, search the Web.

    6. A tape drive can have only one drive and can only handle one job. If your library is capable, you can install a second tape drive to handle another job, but you also need a LEO licence to use the second tape drive.

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  • pkh's avatar
    pkh
    Moderator
    11 years ago

    1.  This is a theoretical speed, but it is very hard to achieve in real life.  Speed is dependent on a lot of factors, like CPU, RAM, network speed, application speed, etc.  Tape writing speed is only one factor.

    There are some tuning that you can do with BE, including tape drives.  See my article below

    https://www-secure.symantec.com/connect/articles/tuning-backup-exec

    2. You can test out the truth of this claim by backing up the same resource to tape with and without compression.  LTO3 does not have hardware compression so the difference should be apparent.

    3. Everybody's speed would be different.  If I tell you that I get better speed, it would be meaningless in your case because you cannot replicate my environment.

    4. No.

    5. A kernel mode drive as the name implies is part of the kernel.  For more details, search the Web.

    6. A tape drive can have only one drive and can only handle one job. If your library is capable, you can install a second tape drive to handle another job, but you also need a LEO licence to use the second tape drive.