Limits on tar for 4.3.3

[dklloyd]

We currently backup our Oracle database datafiles using the tar utility. Some of the files have grown to over 2Gb (on a large file enabled file-system), which according to the 'man' details, tar does not support. The backup does not produce any errors when they are carried out, so is 4.3.3 okay with these files, or will we only find ourselves in a fix if we try to restore?

I have seen information on this site regarding the 2Gb max, but wondered whether this was still the case with 4.3.3?

Many thanks in advance.

dklloyd

 

[victorv]

hi, some questions

1) are you backing up database files or
do you use Oracle export utility and backup
exportd files ?

2) where do you backup them ? /rmt0 , which type of media

3) do you know backup/restore commands in AIX

bye

 

[dklloyd]

Thanks

I'm backing up the database files (each can be over 2Gb), not export files

They are backed up to rmt0 (20Gb tape drive)

I haven't had to use the backup commands to date but I expect I can learn them pronto!

Is this a definate yes then, that tar will not restore the datafiles?

Cheers

dklloyd

 

[victorv]

hi,
I use tar for compatibility with other OS, but
I never used on big file or to save entire filesystem.

Seeing on man, this limitation is not a bug to fix, but is due a "limitations imposed by XPG/4 and POSIX.2 standards."

I belive the problem is not restore them, but they are not on tape.

BACKUP
======
To use backup simply:

#cd /yourdbpath
#find . | backup -ivpf /dev/rmt0

Notes:

1) p stays for Packed (compress) : you can put or omit.
See note on man: "If you specify the -p flag,
only files of less than 2GB are packed"

2) changing dir to path and using find . and not find /xxx
allows you to restore it where you want


RESTORE
=======

#cd /yourdbpath

or

#cd /alternativedbpath

#restore -xvf /dev/rmt0

backup + restore, supports multi volume feature, but probably you don't need with 20Gb !


bye

 

[dklloyd]

Thanks again victorv, I'll give this a go.

Dklloyd