Putting ACFS to work: how to create a mount point in the new Oracle File System

This post is a translation of another one that I’ve originally wrote in portuguese. I’ve decided to share with the international Oracle community through my weblog.

ACFS stands for ASM Cluster File System. ACFS is a new file system created by Oracle that is created on top of an ASM Disk Group. The architecture is very simple and these mount points can contain both general purpose files (except  db files) or Oracle Home binaries, which is very good for sharing binaries.

There are three ways to setup ACFS:

- Web (with Enterprise Manager)

- With  ASMCA (ASM Configuration Assistant) a graphic tool

- or through command line statements

We will show you examples using ASMCA because it’s nicer

Here’s the step-by-step:

1 – We had two 1GB LUNs/Disks for this example with which two raw devices were created:

[oracle@node1 ~]$ cat /etc/rc.local

#!/bin/sh

#

# This script will be executed *after* all the other init scripts.

# You can put your own initialization stuff in here if you don’t

# want to do the full Sys V style init stuff.

touch /var/lock/subsys/local

raw /dev/raw/raw1 /dev/sdb1

raw /dev/raw/raw2 /dev/sdc1

chmod 666 /dev/raw/raw1

chmod 666 /dev/raw/raw2

chown oracle:oinstall /dev/raw/raw1

chown oracle:oinstall /dev/raw/raw2

2 – Now it’s time to call ASMCA:

[oracle@node1 ~]$ . oraenv

ORACLE_SID = [+ASM] ?

ORACLE_HOME = [/home/oracle] ? /u01/11.2.0/grid

The Oracle base for ORACLE_HOME=/u01/11.2.0/grid is /u01/oracle

[oracle@node1 ~]$ asmca &

3 – Create one disk group (DG) with those two raw devices:

4 – We then create a ASM volume on top of this DG, naming it “volumezinho” (we show here several ways of doing so):

There are a few advanced options in ASMCA when you create a volume:

5 – Create a directoy on the ext3 Linux file system so when can mount there the device created by “volumezinho”

[root@node1 ~]# mkdir /u02/oradata/acfs
[root@node1 ~]# chown oracle:oinstall /u02/oradata/acfs

6 – Now let’s create the ACFS mount point. We can choose between one of these two options:

But still you have to mount it manually:

Et voilá!

Now we can go to the directory mounted on the ASM volume formated as ACFS, and create some bogus text file:



[oracle@node1 ~]$ df -m
Filesystem           1M-blocks      Used Available Use% Mounted on
/dev/mapper/VolGroup00-LogVol00 47551     16389     28708  37% /
/dev/sda1                   99        11        83  12% /boot
tmpfs                     1014       662       352  66% /dev/shm
/dev/sdd1                  512       351       162  69% /u02/oradata/cluster-lmc
/dev/asm/volumezinho-486   512       101       412  20% /u02/oradata/acfs/data_volumezinho

[oracle@node1 ~]$ cd /u02/oradata/acfs/data_volumezinho
[oracle@node1 data_volumezinho]$ ll
total 68
-rw-r--r-- 1 oracle oinstall    89 Sep 24 14:33 ficheiro.txt
drwx------ 2 root   root     65536 Sep 24 14:20 lost+found

[oracle@node1 data_volumezinho]$ cat ficheiro.txt


Primeiro ficheiro de texto criado num volume ASM no qual foi montado um ACFS!!!


Yupii!!


[oracle@node1 data_volumezinho]$



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