Isolating LU0 from Binary File

To accomplish this, we will INSTALL a generic 6103 LU, and then when IRIS is not looking, we will swap drives, substituting the MIGRATING.BIN file for the previously installed LU, so we can use some IRIS tools with the new binary file.

sim> SET DKP3 6103
sim> ATTACH DKP3 generic.6103
sim> DO IRIS-D31.SIM

( finish boot sequence and login as MANAGER )

# DSP
FCONFIG 
D1400 ( insure that device 1.0 will be a 6103 drive -- see other docs)
# INSTALL AND CLEAR 1.0 ( When asked, use LU 63. This creates a new IRIS LU on the attached DKP3 file  )
# XGEN ACCESS ( this command flushes the buffer pool, allowing you to safely swap drives )

(swap drives as follows:)

sim> DETACH DKP3
sim> ATTACH DKP3 MIGRATING.BIN

At this point you must be careful what IRIS commands access the drive, because it is not really an LU 63, it is an image of your tape backup which could have all the above issues. Accessing it with the wrong routines could damage the data or crash the running system.

# XGEN STATUS

This command will examine the pseudo LU 63 and provide an analysis of its condition.
Possible responses are:

  • File appears to have a header of x blocks.
  • File appears to be reverse endian
  • File is an IRIS LU

If there is a tape header on the binary, it can be removed with:

# XGEN HEADER

Then refresh the status.

# XGEN STATUS

If the file is reverse endian, it can be corrected with:

# XGEN ENDIAN

Then refresh the status.

# XGEN STATUS

It should be an IRIS LU 0.
Now to validate the integrity of the LU, run the 2 index commands.

# XGEN INDEX1

This will create the textfile 0/XGEN.LIBR which is essentially a dump of the contents of 63/INDEX. Nothing else is examined.
This file can be viewed with #EDIT XGEN.LIBR, or #DISPLAY.
It may be helpful later on if there are any file conflicts.

# XGEN INDEX2

This will overwrite 0/XGEN.LIBR, creating roughly the same data, but only after verifying that the file headers actually exist and match the INDEX entries. Any differences will be noted in the listing. This helps to verify that the LU is complete and likely intact.

( Note: ‘# EDIT‘ is a system line editor. This should be documented elsewhere. But for now, in response to its “*” prompt, the command “66T” will type 66 lines of text on the screen, “66L” will move the marker down 66 lines so you can print the next group, etc. Use “CTL-C” to exit.)

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