What "agent" are you using on your Linux guest?

 

________________________________

From: The IBM z/VM Operating System [mailto:[email protected]] On
Behalf Of Mike Walter
Sent: Thursday, February 25, 2010 2:17 PM
To: [email protected]
Subject: Re: z/VM backup&restore procedure

 


If you format VM DASD from VM using the CPFMTXA EXEC is will ALWAYS
install a Format 5 label, and he few other and absolutely critical
things that VM requires.  If you are not very careful to read the ICKDSF
doc when INITing a VM DASD from MVS, you can easily write a VTOC that
makes it appear that the DASD has scads of free space available.  Do
that just ONE single time on a VM page DASD, and get it mounted (by
accident, of course) on an MVS system as a PUBlic volume, and watch your
VM system crash in seconds!  Not a very good career enhancing move. 

Not mentioned when discussing backing up z/VM from a z/OS system, but
critical... if that z/VM system is up and running, just like with z/OS,
there are open files and databases that may span multiple volumes.
Backing up a running z/VM system from any other system can easily result
in "inconsistent file systems".  That is especially true of backing up
Linux guests from anywhere but an agent on that Linux guest -Linux
heavily caches files in memory, so many open files may not be fully
committed to disk at the time of the backup. 

Either shut down your z/VM system before backing it up from any other
system (z/OS or even z/VM), or prepare for sporadic system, and/or
application failures as the inconsistent filesystems are encountered. 

That said, for over 15 years our z/VM system **used to be** backed up by
jobs on z/OS (and it's forerunners).  Once the restores were completed
at the D.R. site, we ran a CMS filesystem checker on every CMS minidisk,
looking for problems - never had a single one.  WE were very lucky, or
very good, or something else entirely.   

But all that was before Linux guests.  Before we started shutting down
our Linux P.O.C. guests (now down to only one) while backing them up
from CMS, the Linux sysprog (not an immediate believer in the warning)
regularly had trouble restoring from nightly backups.   

Your gun, your foot.  You've been warned. 


Mike Walter
Hewitt Associates
The opinions expressed herein are mine alone, not my employer's. 



"Doug Shupe" <[email protected]> 

Sent by: "The IBM z/VM Operating System" <[email protected]> 

02/25/2010 03:29 PM 

Please respond to
"The IBM z/VM Operating System" <[email protected]>

To

[email protected] 

cc

 

Subject

Re: z/VM backup&restore procedure

 

 

 




Tried this once, ended up having to init the packs from z/OS. needed a
Format 5 label if I recall correctly. 
----- Original Message ----- 
From: Martin, Terry R. (CMS/CTR) (CTR) <mailto:[email protected]>

To: [email protected] 
Sent: Thursday, February 25, 2010 15:49 
Subject: Re: z/VM backup&restore procedure 

Hi 
  
If you have a z/OS system and have connectivity to the z/VM packs you
can run DFDSS full pack backup of all of your CKD packs and use ICKDSF
to restore them. This is what I usually do when I want to copy my system
packs for building a new z/VM LPAR for instance.   
  
Thank You, 
  
Terry Martin 
Lockheed Martin - Citic 
z/OS and z/VM Performance Tuning and Operating Systems Support 
Office - 443 348-2102 
Cell - 443 632-4191 
  
From: The IBM z/VM Operating System [mailto:[email protected]] On
Behalf Of Ivica Brodaric
Sent: Thursday, February 25, 2010 3:33 PM
To: [email protected]
Subject: Re: z/VM backup&restore procedure 
  
  
  
Ivica 
2010/2/26 Pluzhnikov Vsevolod <[email protected]> 
Hello, All! 
Help me please in understanding the correct way of backup/restore z/VM
system (on CKD dasd). I'll need to perform this because of disruptive
upgrade of our DS8300. 
I'm testing now ddrxa. 
 Is it possible to define all 3390 mod9 (540RES, 540SPL, 540PAG,
USER...) dasd to maint  as full-pack minidisks and just backup all of
them on tape? 
You can, but I suggest a separate user, call it SYSDASD, SYSDISK, or
whatever, with password NOLOG. Let that user own all full pack
minidisks. You don't need any other statements in that user's directory
except USER and MDISK for each full pack. Then link from a worker
machine to perform backups. 
  
Can I perform a restore with IPL from tape and just typing new dasd in
output command for restore or it can be done only from z/VM ? 
You can restore by IPLing the tape with DDRXA program on it first, and
then mounting data tapes. To create the tape with ICKDSF, DDRXA and
DIRECTXA on it, do UTILITY UTILTAPE ALL or UTILITY UTILTAPE DDR for just
DDR after accessing MAINT 193. Tape needs to be attached as 181 for
this. You may also put the DDR program at the start of your first backup
tape using MOVEFILE: 
  
1. Mount scratch tape and attach it to your machine as 181 
2. Do the following commands: 
REW 181 
FILEDEF IN DISK IPL DDRXA S 
FILEDEF OUT TAP1 (RECF F LRECL 80 BLOCK 80 
MOVEFILE IN OUT 
  
You may then IPL this tape in your virtual machine for practice or on a
real processor. 
  
Ivica 

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