Stand alone backup

[nipun_2]

Hi,
I am trying to do stand alone backup and wanted to confirm the following sequence of commands

Mine is a common environment cluster and I am tyring to backup the common system disk (dkb0) on the server

shutdown the cluster
start the DCL commands from VMS CD-rom on the server

$$$ INITIALIZE MKA300:sysbk
$$$ mount /override=identification DKB0
$$$ mount /foreign mka300
$$$ backup /image /verify dkb0: mka300:MAY10_05_BACKUP.BCK/SAVE_SET

So this should enable me to do the system backup for my entire system disk files.

I would not like to do incremental backup so I kept the /image backup.

If there is any glitch in the sequence of commands or some better way to use
backup with some other qualifiers (e.g interlock etc.) please let me know

Thanks in Advance.
Nipun

[Uwe Zessin · Accepted solution]

$$$ INITIALIZE MKA300:sysbk

There is a space (" ") missing after the ":".

$$$ mount /override=identification DKB0

I would add /NOWRITE - just a minor additional safety and rather write "DKB0:".

$$$ mount /foreign mka300
$$$ backup /image /verify dkb0: mka300:MAY10_05_BACKUP.BCK/SAVE_SET

I think BACKUP will complain about the tape label. Adding /IGNORE= LABEL_PROCESSING should 'fix' this. You don't need INTERLOCK, because no process has any user files open on this disk.

[Volker Halle]

Nipun,

just some small suggestions:

$$$ MOUNT/OVER=ID/NOWRITE DKB0:

Just to protect your disk, if you would make a mistake and specifiy that disk as the output of your BACKUP command.

$$$ BACKUP ...add /IGNORE=LABEL/BLOCK=65535
and /MEDIA=COMPACTION (if you tape supports this). A larger block size than the default of 8192 bytes can extremely speed up your backup.

Volker.

[Jan van den Ende]

Uwe wrote:


I think BACKUP will complain about the tape label.
/quote>

I do not think so, I know for sure! And not only at the label, for that matter.
The maximum total length of the saveset name is 17 chars (name, ".", extension; all counting).
If not specified with /LABEL=.. , then the label will equal the NAME part of the saveset, and a label has a max length of 6 chars!
And (a matter of taste, and experience) I would include the disk name in the saveset name, where the string "BACKUP" is superfluous.
Using DKB0 in the example would be unkind, because all non-zero SCSI disks have 3-digit numbers.
How about: (your example) DKB0_050510.BCK ( & DKB200_050511.BCK for tomorrow's DKB200).
Just check: exactly 17 chars!
Do not forget /LABEL=

Success.

Proost.

Have one on me.

jpe

[Uwe Zessin]

DKB0: is short for DKB000: (=Target 0, LUN 0). OpenVMS is lazy :-)

I haven't specified long saveset names on tape for a long time, but I recall that BACKUP or some other component in VMS used to silently truncate the name.

[Jan van den Ende]

Uwe,

just try!

When one of us recently changed the savesetname algorithm and came to an over-17 length result, it just balked.

I am pretty sure that it was after we changed to SAN, ie, we were already at VMS 7.3-2

Proost.

Have one on me.

jpe

[Uwe Zessin]

Sorry, don't have a tape drive connected.

[Wim Van den Wyngaert]

If your tape has been used before, I would add /dens=xxx to the init command (xxx=highest density available for your drive).

Only the init command can change the density of the tape. So, if your tape was previously used on an older tape drive, you would loose speed and capacity.

Wim

[Antoniov.]

For me, /IGNORE=INTERLOCK may be useless but I use it.
If backup some system file, backup could stop.

Antonio Vigliotti

[Volker Halle]

Antonio,

this thread is about STANDALONE backup. Using /IGNORE=INTERLOCK would not be applicable here, as files cannot be open for write on the CD.

Volker.

[Uwe Zessin]

Volker,

> as files cannot be open for write on the CD.

Somehow I doubt he wants to backup his CD ;-)

But perhaps you meant the real system disk. At least I did, when I wrote
: You don't need INTERLOCK, because no process has any user files open on this disk.

[Volker Halle]

Uwe,

how about:

...as files cannot be open for write when booted from the CD.

Then I don't have to retract the whole sentence ;-)

Sorry,

Volker.

[nipun_2]

Hello All,
Thanks for the replies. I will be trying the commands tonight. Mounting and Initializing sequence as well as the backup qualifiers were my main concern.

so I will be doing the following

$$$ INITIALIZE MKA300: sysbk
$$$ mount /override=identification /nowrite DKB0
$$$ mount /foreign mka300
$$$ backup /image /verify /ignore=label dkb0: mka300:MAY10_05_BACKUP.BCK/SAVE_SET /block=65535

I was a bit confused as to where the block size and /ignore should be so I checked the docs. Please let me know if the position is wrong.

I am not sure about the label should I do /ignore=label or is there someplace I can include the label name(sysbk). In future if it comes to data retrieval would it create any problems?


Also since this is a standalone backup. I was wondering how much time and size it would take. Is there a way I can time the entire operation so that in future I have an idea.

And if I know the size I can then decide whether I can use the same tape or have to use a new one each time.

[Volker Halle]

Nipun,

if you want to, you can specify the label on the BACKUP command line with /LABEL=SYSBK
- by default, BACKUP will take the first 6 characters of the saveset name as the label. Then you won't need to specify /IGNORE=LABEL.

You can time the BACKUP by noting the time when you start it. After you've started the BACKUP, just type SHOW TIME - this command will go into the OpenVMS typeahead buffer and will be executed, once backup is finished and returns to the DCL prompt (except if it would ask for a continuation tape).

You can get an idea of the size of the data to be backed up by taking the difference between total blocks and free blocks of the disk and reducing that by the size of all files marked /NOBACKUP (e.g. SYSDUMP.DMP, PAGEFILE.SYS and SWAPFILE.SYS)

Volker.

[Jan van den Ende]

Nipun,

some remarks.

As Wim wrote: to get the most out of your tape, you have to specify so on the INITialyse.
Most current tapedrives support compaction. To use that ( 3 - 4 times as much data on a tape) you MUST INIT with /MEDIA=COMPACT
Other drives support different densities. Then, to use the highest, you MUST specify that on INIT by /DENS=.
If you cannot find what is needed in your case, please tell us the exact type & model of your drive, and I am sure someone over here will know, and answer.

Like I wrote, your _ENTIRE_ saveset name may not exceed 17 chars. Yours is 19. It just will not work. Please re-read my entry above.

Like Uwe already indicated, let me re-phrase: the label you gave the tape with INIT (sysbk in your example) _MUST_ be the same as the /LABEL=.. in your BACKUP command.

Success.

Proost.

Have one on me.

jpe

[Ian Miller.]

also put /media=comp on the backup command to ensure you get compaction on your tape drive. If you have a listing file on the backup
(moount one of the other disks and write it there) then at the end of the listing file it will tell you how many block and how many files.

[nipun_2]

Okay for now I will stick with no label

So
$$$ INIT /media=compact MKA300:sysbk
$$$ mount /override=identification /nowrite DKB0
$$$ mount /foreign mka300
$$$ backup /image /verify /ignore=label dkb0: mka300:MAY10_05_BACKUP.BCK/SAVE_SET /block=65535

Regarding my tape drive
I found a link on e-bay that looks similar and I am also putting down the details after the link

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=39978&item=5193908789&rd=1


This is what I found from our external scsi tape drive


The tape drive
40/808 GB DLT
HP series 3306

Maxell
Tape 40 GB/80 GB* 557mt 1828ft
DLTtape IV

*Assumes 2:1 Data Compression. Capacity is Drive Dependent.

[nipun_2]

oops I forgot to edit the saveset name

$$$ backup /image /verify /ignore=label dkb0: mka300:MAY10_05_BK.BCK/SAVE_SET /block=65535

[Ian Miller.]

In this command
INIT /media=compact MKA300:sysbk

sysbk is the label and there should a space after the :
INIT /media=compact MKA300: sysbk

You could have
/LABEL=SYSBK/MEDIA=COMP on your BACKUP command
instead of /ignore=label

[nipun_2]

So
$$$ INIT /media=compact MKA300:sysbk
$$$ mount /override=identification /nowrite DKB0
$$$ mount /foreign mka300
$$$ backup /image /verify /ignore=label /media=compat dkb0: mka300:MAY10_05_BK.BCK/SAVE_SET /block=65535

[nipun_2]

Hi Ian,
Thanks for pointing out the space I put it but somehow in copy paste it changes. I apparicate you looking at the finer details.


So I will include

$$$ backup /image /verify /LABEL=SYSBK/MEDIA=COMP dkb0: mka300:MAY10_05_BK.BCK/SAVE_SET /block=65535

/LABEL=SYSBK/MEDIA=COMP on your BACKUP command
instead of /ignore=label

Regarding file size I am not clear of the listing file. But for now I will not worry about the size as I want to get jsut the backup done in the right manner the second time I do backup I will look into size aspect.
Nipun

[Steve Nimr]

Nipun,

On VMS 6.2 it complains about the location of the /media=compact qualifier. I don't have later versions of VMS so I don't know if it's relative but in this version you need that qualifier after the tape device.

I'm doing a standalone b/u on a 6.2 disk right now. I can give you the tape time in about 6 hours. I've also done tests to disk. Here are the disk times for a 4403591 block saveset- with rms/buf=4/block=100 it took 01:14:00 without rms buffers 05:26:00.

Steve

[Wim Van den Wyngaert]

You MUST specify /DENS=DLT8000 (or whatever) or you will get the density used on the previous init command (e.g. on your 8 years old drive). So only specifying compaction is not enough. We noticed this because our new drive was not getting its capacity during backup.

Wim@home

[Robert_Boyd]

An easy way to set this up for ease of getting it right with time stamps -- create a command procedure that contains all of the commands and insert

$ SHOW TIME

after every command. You can have the command procedure in the [000000] directory of the disk you are backing up -- so then when you boot from the CD you can do something like this:

$ mount/override=ID/nowrite :
$ @:[000000]standalone_backup

You could make the command procedure smart enough to figure out the name of the saveset for you.

In the past, I've found it useful to put the device name into the saveset name for ease of remembering where the saveset came from:

20050510_dkb300. would be a useful saveset name in my way of looking at it.

Another thing that I have seen improve the backup performance in addition to using the maximum block size (65024) is to increase the XOR group size with the /GROUP_SIZE. I usually use something like /GROUP_SIZE=35 or 40. This means that less of the tape is being consumed by the extra blocks for error recovery.

Robert

[Steve Nimr]

Hi,

The tape backup was the fastest. It took under 35 minutes. I used:
$ backup /image /verify /ignore=label dkd1: -mkb500:sys.sav/save/block=65535/media=compact

Configuration is:
AS4100 VMS6.2
TZ88 tape drive
When the disk was the destination
HSZ70 controller to a JBOD set.

I did it twice to verify my times and compared the listings from the disk save to the tape save.