reduce filesystem size within rootvg

reduce filesystem size within rootvg

Post by Jie W » Thu, 06 May 1999 04:00:00



I need to change file system sizes in my root volume group. I want to
increase /root and /usr. but there is no diskspace within rootvg, so I
decide to reduce the /home to create some space. Please give me any
suggestion that you think I should conside.

In one of the IBM redbook, there is an example of reducing /usr size.
The steps are:
1) backup the /usr fs
2) umount /usr and then remove it
3) create a new /usr fs with reduced size
4) restore

On another publiction, however, it is stressed that the above procedure
can only be applied on user fs outside of rootvg. The procedure
recommended is:
1) mkszfile to create file /.fs.size
2) edit /.fs.size to modify the fs size
3) umount all user fs
4) varyoff all user vg and export them
5) mksysb
6) install system from the backup
7) import user vg and vary on them
8) mount all

which one is correct? I appreciate any suggestion

Jie

 
 
 

reduce filesystem size within rootvg

Post by Jie W » Thu, 06 May 1999 04:00:00


I need to change file system sizes in my root volume group. I want to
increase /root and /usr. but there is no diskspace within rootvg, so I
decide to reduce the /home to create some space. Please give me any
suggestion that you think I should conside.

In one of the IBM redbook, there is an example of reducing /usr size.
The steps are:
1) backup the /usr fs
2) umount /usr and then remove it
3) create a new /usr fs with reduced size
4) restore

On another publiction, however, it is stressed that the above procedure
can only be applied on user fs outside of rootvg. The procedure
recommended is:
1) mkszfile to create file /.fs.size
2) edit /.fs.size to modify the fs size
3) umount all user fs
4) varyoff all user vg and export them
5) mksysb
6) install system from the backup
7) import user vg and vary on them
8) mount all

which one is correct? I appreciate any suggestion

Jie

 
 
 

reduce filesystem size within rootvg

Post by Jie W » Thu, 06 May 1999 04:00:00


I need to change file system sizes in my root volume group. I want to
increase /root and /usr. but there is no diskspace within rootvg, so I
decide to reduce the /home to create some space. Please give me any
suggestion that you think I should conside.

In one of the IBM redbook, there is an example of reducing /usr size.
The steps are:
1) backup the /usr fs
2) umount /usr and then remove it
3) create a new /usr fs with reduced size
4) restore

On another publiction, however, it is stressed that the above procedure
can only be applied on user fs outside of rootvg. The procedure
recommended is:
1) mkszfile to create file /.fs.size
2) edit /.fs.size to modify the fs size
3) umount all user fs
4) varyoff all user vg and export them
5) mksysb
6) install system from the backup
7) import user vg and vary on them
8) mount all

which one is correct? I appreciate any suggestion

Jie

 
 
 

reduce filesystem size within rootvg

Post by AIXMight » Fri, 07 May 1999 04:00:00


well you got lucky!  /home is not really part of AIX.  it's usually the homes
of your users.  that said, as long as you don't have any users on the system,
just backup /home, umount, rmfs, mklv, crfs, mount, restore, and you should be
good to go.  no downtime (at least reboot) is needed...

/usr is another story...  you do need some downtime to shrink it...

Orphy! :-)
Dallas, TX


Quote:>I need to change file system sizes in my root volume group. I want to
>increase /root and /usr. but there is no diskspace within rootvg, so I
>decide to reduce the /home to create some space. Please give me any
>suggestion that you think I should conside.

>In one of the IBM redbook, there is an example of reducing /usr size.
>The steps are:
>1) backup the /usr fs
>2) umount /usr and then remove it
>3) create a new /usr fs with reduced size
>4) restore

>On another publiction, however, it is stressed that the above procedure
>can only be applied on user fs outside of rootvg. The procedure
>recommended is:
>1) mkszfile to create file /.fs.size
>2) edit /.fs.size to modify the fs size
>3) umount all user fs
>4) varyoff all user vg and export them
>5) mksysb
>6) install system from the backup
>7) import user vg and vary on them
>8) mount all

>which one is correct? I appreciate any suggestion

>Jie

 
 
 

reduce filesystem size within rootvg

Post by Johan Van Mengse » Fri, 07 May 1999 04:00:00


The procedures you're describing are correct : first procedure is valid
for every filesystem
that you can unmount while the system is online. This excludes /, /usr,
/tmp and sometimes /var.
All other filesystems should be unmountable.
For the other filesystem,  procedure 2 is the right way although it misses
a few steps : create a mksysb backup
with modified .fs.size and re-install your rootvg.

If you don't like playing around with tapes/backup/restore you should
check out http://www.compunix.com There
are commercial utilities available for shrinking filesystems. Only pre-req
is that the filesystem is unmounted so
that would require reboot/downtime when reducing /, /usr or /tmp.

Regards,

Johan Van Mengsel


> I need to change file system sizes in my root volume group. I want to
> increase /root and /usr. but there is no diskspace within rootvg, so I
> decide to reduce the /home to create some space. Please give me any
> suggestion that you think I should conside.

> In one of the IBM redbook, there is an example of reducing /usr size.
> The steps are:
> 1) backup the /usr fs
> 2) umount /usr and then remove it
> 3) create a new /usr fs with reduced size
> 4) restore

> On another publiction, however, it is stressed that the above procedure
> can only be applied on user fs outside of rootvg. The procedure
> recommended is:
> 1) mkszfile to create file /.fs.size
> 2) edit /.fs.size to modify the fs size
> 3) umount all user fs
> 4) varyoff all user vg and export them
> 5) mksysb
> 6) install system from the backup
> 7) import user vg and vary on them
> 8) mount all

> which one is correct? I appreciate any suggestion

> Jie