Tape Backups
Although most observers prefer to backup data using the CD/DVD writers or 'scp' data to their home institution, tape drives are available to observers for saving data on magnetic media. There are 8 mm Exabyte, DAT, DLT and Ultriumtape drives available to the observers. The tape drives are located in Remote Ops 1 & 2 and the Pre/Post Observing Room. See below for a list of computers and their locations where tape dirves are accessible.
Computer Location Tape_Drives
pohue Remote Ops II 8mm(Exabyte), DLT, Ultrium
pupukea Remote Ops I 8mm(Exabyte)
waiehu K2 Pre/Post-Observing Space DAT, 8mm(Exabyte)
moomomi K2 Pre/Post-Observing Space DAT, 8mm(Exabyte)
mokulau Remote Ops I 8mm(Exabyte)
hamoa Remote Ops II 8mm(Exabyte)


Keck does not supply tapes for any of the devices listed above. If you prefer to store data on a magnetic tape, you will need to bring blank tapes to Keck.

Writing a tape

Tapes are written using a script called 'mktartape' which is available from HQ machines. 'mktartape' saves directory trees to tape in Unix tar format. This task provides a virtually foolproof method for writing backup tapes in Unix tar format. Significant features:
  • supports all tape formats (Exabyte, DAT, DLT, and LTO)
  • warns user if no tape drives are attached to the current machine and offers a list of alternative machines with tape drives
  • allows observer to select any tape drive on the current machine without needed to know the name of the tape drive
  • prints list and status of all tape drives attached to the current machine
  • checks status of tape before trying to write to verify whether drive is already in use, tape is inserted and rewound
  • allows user to select from available legal tape densities
  • allows user to append new files to those already on tape
  • can write multiple data directory trees to tape in one pass, putting each into a separate tarfile
  • verifies the existence of the data directories entered by user
  • after writing data to tape can (optionally) verify tape while creating a tape log
  • optionally rewinds and ejects tape at completion of writing

Usage

mktartape
    To run mktartape, type 'mktartape' on any HQ computer and the script will walk you through each step. Below is an example of an mktartape session.

Examples

Here is a sample run (user input in bold):
gwirth@kapoho:~/tmp% mktartape
	----------------------------------------------------------------
	Welcome to MKTARTAPE, a program for creating tapes of your data.
	----------------------------------------------------------------

No tape devices are attached to this machine (kapoho).  Would you like
to try running this program on a different computer which has a tape drive
available? [y]: y

Okay, here's a list of the available machines and tape drives:


N  Computer     Location                            Tape_Drives       
-  --------     --------                            -----------       
1  pohue        Remote Ops II                       8mm(Exabyte), DLT, Ultrium
2  pupukea      Remote Ops I                        8mm(Exabyte)      
3  waihee       Room 109 (K2 Pre/Post-Observing)    DAT, 8mm(Exabyte) 
4  moomomi      Room 110 (K1 Pre/Post-Observing)    DAT, 8mm(Exabyte) 
5  mokulau      Remote Ops I                        8mm(Exabyte)      
6  hamoa        Remote Ops II                       8mm(Exabyte)      
7  None of the above --- quit!                                                       
Please select an option by number [7]: 4

Okay, spawning /home/kapoho/gwirth/bin/mktartape on moomomi...

	----------------------------------------------------------------
	Welcome to MKTARTAPE, a program for creating tapes of your data.
	----------------------------------------------------------------

Here are the tape devices available on moomomi:

   N  Type            Device          Busy?      Tape_in?   Rewound?  
   -  ----            ------          -----      --------   --------  
   0  DAT             /dev/rmt/0      No         Yes        Yes       
   1  8mm(Exabyte)    /dev/rmt/1      No         No         No        
   2  None of the above --- quit!                                                 

Please select an option by number [2]: 0

The tape drive appears to be online and the tape is rewound to the beginning.
Your options are:
(B)egin recording here, or
(S)kip past any existing files on the tape and record from there.
So which will it be? [b]: b

Please select a data format.  Options are:
	[L]ow
	[M]edium
	[H]igh
	[C]ompressed
Which would you like? [l]: l

Enter name of first data directory to save to tape (RETURN to end list):
> /h/gwirth/tmp/data1
Directory /h/gwirth/tmp/data1 exists and is accessible; adding it to list...

Enter name of next data directory to save to tape (RETURN to end list):
> /h/gwirth/tmp/data2
Directory /h/gwirth/tmp/data2 exists and is accessible; adding it to list...

Enter name of next data directory to save to tape (RETURN to end list):
> /h/gwirth/tmp/data3
Directory /h/gwirth/tmp/data3 exists and is accessible; adding it to list...

Enter name of next data directory to save to tape (RETURN to end list):
> /h/gwirth/tmp/data4
ERROR: directory '/h/gwirth/tmp/data4' not found; please try again

Enter name of next data directory to save to tape (RETURN to end list):
> 

Should I generate a logfile listing of the contents of the tape when I am done?
This can help verify that things went smoothly, but will take extra time. [n]: y

Enter name of logfile to create [mktartape.log]: 

Should I rewind and eject the tape when done? [y]: y

Before I start writing the tape, please verify the information below:
	Hostname:             	moomomi
	Tape device name:     	/dev/rmt/0lbn
	Tape device type:     	DAT
	Density:              	[L]ow
	Directories to store: 	/h/gwirth/tmp/data1
				/h/gwirth/tmp/data2
				/h/gwirth/tmp/data3
	Logfile:              	mktartape.log
	Rewind before writing:	No
	Skip to EOM marker:   	No
	Eject at end:         	Yes
Should I begin? [y]: y

------------------------------------------------------------------------
Storing data from directory /h/gwirth/tmp/data1
------------------------------------------------------------------------
./
foo1.fits

------------------------------------------------------------------------
Storing data from directory /h/gwirth/tmp/data2
------------------------------------------------------------------------
./
foo2.fits

------------------------------------------------------------------------
Storing data from directory /h/gwirth/tmp/data3
------------------------------------------------------------------------
./
foo3.fits

Done writing data to tape.
Rewinding tape to create logfile...done.
Generating listing for file 1...done.
Generating listing for file 2...done.
Generating listing for file 3...done.

Rewinding and ejecting tape...done.

	----------------------------------------------------------------
		      Finished writing tar tape
	----------------------------------------------------------------
              
    

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