Format tape on MSL G3 series

[saad7]

Hi All,

I would like to format tape on, its ultrium 4 on MSL Library, i have checked all the options. Our is SAP system running on HP-UX 11.23.
Kindly suggest how can i format tape as DP is not configured.

Regards!!

[Patrick Wallek]

Formatting of tapes is not normally required.

I don't know of any backup utilities that require a tape to be formatted.

[saad7]

Hi Pattrick,

Thanks for your quick responce.

we can format the tape, if OMNI Data Protector is configured. In my previous organisation, i use to format tape which is one year old to reuse the same tape for BAkups.
Here ODP is not been configured. While taking backup of SAP server am getting the message as Backup Finished with warnings. In log its showing as "BR0019W Volume size or disk capacity reached - not all offline redo log files will be saved"
am using ultrium4 which is 1.6 TB and our database is 210 GB.
If i format tape i get the whole space, or let me know how can we find the availbale space on that perticular tape.

Regards!!

[Bill Hassell]

Formatting a tape is an application idea -- HP-UX has no such requirement. Data Protector (OmniBack) formats tapes to keep track of them in it's database. Since DP is not installed on your current system, there is no formatting option.

> While taking backup of SAP server ...

So you must be using a different program to backup this server.

> If i format tape i get the whole space ...

You don't create space with a format command. It is only used to put a label on the tape and optionally perform some tests on the quality of the tape.

> am using ultrium4 which is 1.6 TB

Unfortunately all tape drives for the last 20 years have been overrated by every manufacturer. Your tape stores 800 GB -- period. By reducing repetitive data through data compression, less data is sent to the tape and it 'appears' to hold more than 800 GB. However, you cannot control the amount of compression -- it is totally dependent on your data. It might be totally random and the compression will be 1:1, or it might be mostly empty database files and the compression ratio might be 50:1 in which case your tape can store 40 TB. Here are the details:

http://en.wikipedia.org/wiki/Ultrium

> our database is 210 GB ...

How is this measured? By the database it self, or did you use ll or du to measure the size of the files? The du command will show the occupied space while the ll command will show the logical space. Most databases use data files in 'sparse' mode where only selected records are written and the rest is undefined. Copy one of these files and the missing (actually: undefined) records will be supplied as a stream of zeros, making the copy much larger than the original.