Raw devices files

Hi,
I already created raw devices on database 10g R2. How can make those raw devices available to oracle user?
Best Regards
Yassin
Message was edited by:
Yassin

Yes, the os is Sun Solaris and my question how can
create tablespaces on raw devices.create tablespace abcd datafile '/dev/rdsk/c0t0d0s4/abcd.dbf' size ...
This is an example only, adapt it to your needs! Never fill up the rawdevice completely, leave some space for emergency situations. A different question: why are you using raw devices? What's the output of uname -a? Beginning with Solaris 8 (don't know the maintenance level), you can mount filesystems with the direct io option which gives you almost raw device performance with all advantages of a file system.
Thank you.
Yassin
Message was edited by:
Yassin

Similar Messages

RAW DEVICE와 FILE SYSTEM 간에 오라클 데이터화일 이동하기

제품 : ORACLE SERVER
작성날짜 : 1999-11-30
RAW DEVICE와 FILE SYSTEM 간에 오라클 데이터화일 이동하기
======================================================
유닉스 명령이 dd를 이용하여 오라클 데이터화일을 Unix File System과 Raw
Device 간에 이동할 수 있으나, 플랫폼 별 Raw Device의 특성으로 인하여 주의할
점이 있다. 만일 잘못된 이동으로 인하여 데이터베이스가 기동하지 못하면,
ORA-7366 (sfifi: invalid file, file does not have valid header block.)
에러가 발생할 수 있다.
예를 들어 Digital unix의 경우는 raw device에 64k OS 헤더가 필요하므로 dd
명령어 옵션 중 iseek와 oseek를 활용하여야 한다.
다음은 예제를 통하여 데이터화일을 Raw Device에서 Unix File System으로
이동하는 절차이다.
(운영 현황)
- 현재의 위치: /dev/rdsk/c0t15d0s7
- 이동할 위치: /oracle/file/system.dbf
- 화일의 크기: 488636416 bytes <--- V$DATAFILE.BYTES column 값!
- DB_BLOCK_SIZE: 2048 bytes
(준비 단계)
1. Oracle 블럭 수 계산:
BYTES / DB_BLOCK_SIZE = 488636416 / 2048 = 238592 (블럭)
2. O/S file header 블럭 추가:
238592 + 1 = 238593 (블럭)
: "ls -l /oracle/file/system.dbf" 명령으로 확인 가능하며, O/S file
header는 1블럭으로 항상 일정함.
3. Raw Device OS header 블럭 계산:
64K / DB_BLOCK_SIZE = 65536 / 2048 = 32 (블럭)
: 사용할 dd 명령어 중 블럭의 크기를 DB_BLOCK_SIZE(2048바이트)로 할
예정이므로 2048로 나누어야 함.
(명령어 형식)
$ dd if=<raw device> of=<UFS file> bs=<oracle blocksize>
iseek=<blocks to skip> count=<total count>
(명령어 수행 절차)
(1) SVRMGR> STARTUP MOUNT
(2) SVRMGR> !dd if=/dev/rdsk/c0t15d0s7 of=/oracle/file/system.dbf
bs=2048 iseek=32 count=238593
(3) SVRMGR> ALTER DATABASE RENAME FILE '/dev/rdsk/c0t15d0s7' TO
'/oracle/file/system.dbf';
(4) SVRMGR> ALTER DATABASE OPEN;
========================================================================
반대로 Unix File System에서 Raw Device로 이동하는 명령어 형식은 아래와 같다.
(명령어 형식)
$ dd if=<UFS file> of=<raw device> bs=<oracle blocksize> \
oseek=<blocks to skip> count=<total count>
유사한 방식으로 데이타 화일 뿐 아니라 리두 로그 화일도 이동할 수 있다.
[주의] Raw Device의 블럭 헤더의 크기는 OS마다 다를 수 있으므로 플랫폼
벤더사에 미리 확인한 후 작업하여야 한다.

OPS/RAC Vs Raw Device/File System

Hello, firts to all, I want to know what is OPS/RAC and Raw Device/File System.
And then know the diferens between both.
I apologize for my english.
Thanks.

OPS is Oracle parallel server was available up to Oracle 8i and RAC is Real application cluster is available from Oracle 9i.
Raw device is just presenting the disk to server and using it. File system is presenting disk more transparent and managable form using OS or third party software.
You need to refer respective documents to know them in detail.
Ashok

Can you please advice on RAW device file permission change to crw-r-----

Currently we have Oracle9i (9.2.0.5) RAC on IBM AIX 5.2 system with 2 node cluster.
We use the RAW device for Oracle data file default file permission for raw device is crw-rw---- can we change to crw-r-----(remove write permission from group).
Can you please advice.
Thanks & Regards

Hi,
What is your intention behind this? If protection, there can ve other ways possible.
Regards,
Ankit

How to create DIR/File on a raw device in RAC environment.

Hi all,
I use a shell script to create DIR and File on a raw device also it creates schema and tablespaces.
I am facing problem in creating DIR and Files on raw device.
One more thing, can multiple tablespaces be created on a raw device.
Thanks & regards,
Sanjeev

Thanks for the response. Please help me further.
About the Script - It asks for the path for creating DIR and uses shell command to create DIR. Later same path and DIR name is used to create Oracle DIR. Now in place of absolute path raw device name is passed. The same script is also used for creating tablespaces and schema.
There is second script that is .sql script that creates external table in the newly created schema. All this has been working fine on single instance Oracle server. we have tested many times but fails in RAC environment when we use raw device.
Question is - If I use filesystem will the external table's flat files and Directories be accessible to all the instances.
I have one application written in java that would be clustered and running on these oracle servers. This application would be accessing those external tables and their flat files. Will there be a problem accessing these flat files accross the instances.
Regards,
Sanjeev.

Convert Raw Device to file system based file systems for datafiles [HP-UX]

Hello experts,
Once again in seek of guidance..
I am in the process of migrating my database (Oracle 7.2.3 on HP-UX 10.20 to Oracle 8.1.7 64-bits on HP-UX 11).
Amongst one of our steps is to convert our RAW Device datafiles to File System based files within the same server and version - Oracle 7.2.3 on HP-UX 10.20.
E.g. /dev/vg00/rlvol1 to become /d01/oradata/cmtdb/tbs1.dbf
Is this something possible?
Can i just do the following:
a. Shutdown database (normal)
b. dd if=/dev/vg00/rlvol1 of=/d01/oradata/cmtdb/tbs1.dbf bs=20k
c. chown oracle7:dba /d01/oradata/cmtdb/tbs1.dbf
d. svrmgrl> startup mount
e. alter database rename file '/dev/vg00/rlvol1' to '/d01/oradata/cmtdb/tbs1.dbf'
f. alter database open.
Thanks very much for your replies.
Please tell me about possible problems that i can anticipate.
Best Regards
Yogeeraj

Hello experts,
Once again in seek of guidance..
I am in the process of migrating my database (Oracle 7.2.3 on HP-UX 10.20 to Oracle 8.1.7 64-bits on HP-UX 11).
Amongst one of our steps is to convert our RAW Device datafiles to File System based files within the same server and version - Oracle 7.2.3 on HP-UX 10.20.
E.g. /dev/vg00/rlvol1 to become /d01/oradata/cmtdb/tbs1.dbf
Is this something possible?
Can i just do the following:
a. Shutdown database (normal)
b. dd if=/dev/vg00/rlvol1 of=/d01/oradata/cmtdb/tbs1.dbf bs=20k
c. chown oracle7:dba /d01/oradata/cmtdb/tbs1.dbf
d. svrmgrl> startup mount
e. alter database rename file '/dev/vg00/rlvol1' to '/d01/oradata/cmtdb/tbs1.dbf'
f. alter database open.
Thanks very much for your replies.
Please tell me about possible problems that i can anticipate.
Best Regards
Yogeeraj

Is database using File system, RAW devices or ASM?

Hi there
Is is possible to find out if the database is using File system, RAW devices or ASM for storage?
I think for ASM, we can tell by querying the V$DATAFILE view if it has ' DATA ' or something like that (a name that has ' ' prefixed to it). Is this the only way? How about other sotrage types (RAW and Filesystem)?
Thanks in advance!

user12033597 wrote:
I think for ASM, we can tell by querying the V$DATAFILE view if it has ' DATA ' or something like that (a name that has ' ' prefixed to it). Is this the only way? How about other sotrage types (RAW and Filesystem)?V$DATAFILE or DBA_DATA_FILE
Raw depends on your OS - in *nix, likely something like /dev/sdc1
ASM depends on ASM and will include + and will follow an ASM pattern, such as described http://docs.oracle.com/cd/B19306_01/server.102/b14200/clauses004.htm
File depends on OS - in *nix, likely start with a '/' and NOT be in /dev or /proc. In Winders start with C:\ or some other disk path.
Nicely discussed in the docs in the Administrators Guide found at http://tahiti.oracle.com

Raw Device Backup to file system(OPS 8i)

Hi
Our currently setup is
Oracle database 8.1.6 (Oracle Parallel Server) Two Node
Noarchive Mode
Solaris 2.6
all database file ,redo logfiles,controlfiles under raw device.
database size 16 G.B
oracle block size 8192
currently we are using only export backup of oracle.
But now i want to take cold backup of oracle database to disk.
cold backup Raw --> Disk
How we can take cold backup with dd command and skip parameter ?
Is anybody have practical idea of dd command with skip parameter.
Thanks and regards
Kuljeet pal singh

you can use ufsdump instead of dd

Raw devices versus Cluster File Systems in RAC 10gR2

Hi,
Does anyone using cluster file systems in a RAC 10gR2 installation, specifically IBMs GPFS?
Ive visited a company that is running RAC 10gR2 in AIX over raw devices. Why someone would choose to use raw devices , with all the problems to administer , when all the modern file systems are so powerful? Is there any issues when using cluster file systems + RAC? Is there considerable performance benefits when using raw devices with RAC ?
I´ve always used Oracle stand alone instances over file systems (since version 7) , and performance was always very good. I´ve tested raw devices almost 10 years ago , and even in that time (the hardware today is much better - SAN , 15K rpm disks , huge caches - and the file systems software today is much better) the cost to administer it does not compensate the benefits (only 5% more faster than file systems in Oracle 7).
So , besides any limitations imposed by RAC , why use raw devices nowadays ?
Regards,
Antonio Belloni

Hi,
spontaneously, my question would be: How did you eliminate the influence of the Linux File System Cache on ext3? OCFS2 is accessed with the o_direct flag - there will be no caching. The same holds true for RAW devices. This could have an influence on your test and I did not see a configuration step to avoid it.
What I saw, though, is "counter test": "I have tried comparing simple file copies from an OS level and the speed differences are not apparent - so the issue only manifests itself when the data is read via an oracle db." and I have no good answer to that one.
Maybe this paper has: http://www.oracle.com/technology/tech/linux/pdf/Linux-FS-Performance-Comparison.pdf - it's a bit older, but explains some of the interdependencies.
Last question: While you spent a lot of effort on proving that this one query is slower on OCFS2 or RAW than on ext3 for the initial read (that's why you flushed the buffer cache before each run), how realistic is this scenario when this system goes into production? I mean, how many times will this query be read completely from disk as opposed to use some block from the buffer? If you consider that, what impact does the "IO read time from disk" have on the overall performance of the system? If you do not isolate the test to just a read, how do writes compare?
Just some questions. Thanks.

Database Data files on RAW Devices

Hi,
I'm creating a database and wish to locate the tablespaces on a raw device.
How do I specify the datafiles for the tablespaces on the raw device.

> Any reason for moving to raw device?
I actually prefer raw devices and ASM over using cooked file systems.
By default RAW devices eliminate the "interference" of the kernel. It does not manage a file system on the device. There are no other foreign processes that can use that raw device (as is often the case with cooked devices). There is no o/s file system cache for that device. A physical I/O on the Oracle side means a dinkum physical I/O and not a maybe-logical-I/O-from-the-file-system-o/s-cache.
There is no need for me as DBA to manage that file system according to OFA standards (ASM does it for me). There is no need for me to go through the learning curve of using a 3rd party volume manager. I have features like automated load balancing while the instance is up and running.
Yes, there is an argument to be made for just how much of a performance improvement in I/O one can get from a raw device versus a cooked file system. But I/O performance is not the only consideration.

IS RAW DEVICES SUPPORTED OVER A CLUSTER FILE SYSTEM

Can raw partions be defined for datafiles after having choosen Cluster file system as storage option for database while creating fresh database using
DBCA?

> Do update on how the partitions have to be defined in either cases?
For both ASM and OCFS, a partition must exist on the disk - it can be of any partition type. Does not matter. Simply that the s/w references a partition and not an entire disk.
So for example, /dev/sdaf and dev/sdag are two shared devices on the cluster (LUNs on the SAN or whatever).
You create a partition on each. E.g
# fdisk -l /dev/sdaf
Disk /dev/sdaf: 36.5 GB, 36573020160 bytes
255 heads, 63 sectors/track, 4446 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Device Boot Start End Blocks Id System
/dev/sdaf1 1 4446 35712463+ 83 LinuxTo use the first device as a OCFS device, you need to build an ocfs file system on it using mkfs.
And then it can be mounted as a "normal" cooked file system mount. Remember that /etc/fstab needs to be updated for mounting it on startup.
To use the second device for ASM, you have two choices. If you have the ASMlib kernel module installed, you can use that to configure a volume label and assign it for use by ASM.
Alternatively, you simply map the device (partition) to a raw device for detection by ASM. E.g.
# raw /dev/raw/raw1 /dev/sdag1Of course, you also need to make this permanent by updating the raw device list config file so that this mapping is performed on reboot. On Linux, this is the /etc/sysconfig/rawdevices file. Also remember that the user and group access for the logical raw device created, must allow ASM full access to it (e.g. use chmod oracle.dba /dev/raw/raw1).
In a nutshell, this is how to raw devices are used as ocfs and asm volumes. (on RHEL specifically, but I expect no major differences in this approach on other o/s's)

Raw device for oracle 8.1.7 on AIX 4.3.3

Hi there,
I am trying to use a raw device on AIX 4.3.3 for ORACLE 8.1.7.
I have created a raw device /dev/or_system
brw-rw---- 1 oracle dba 54, 1 Mar 04 10:44 or_system
but it is not possible to create a datafile on it :
SVRMGR> create database "GLM"
maxinstances 8
character set "WE8ISO8859P1"
datafile '/dev/or_system' size 150M REUSE
logfile
GROUP 1 ('/oracle/GLM/redo/log1.ora') size 100M,
GROUP 2 ('/oracle/GLM/redo/log2.ora') size 100M,
GROUP 3 ('/oracle/GLM/redo/log3.ora') size 100M,
GROUP 4 ('/oracle/GLM/redo/log4.ora') size 100M;
create database "GLM"
ORA-01501: CREATE DATABASE failed
ORA-01519: error while processing file '?/rdbms/admin/sql.bsq' near line 407
ORA-00604: error occurred at recursive SQL level 1
ORA-01119: error in creating database file '/dev/or_system'
ORA-27038: skgfrcre: file exists
SVRMGR>
The ORA-27028 in exact this situation was reported as a bug in prior ORACLE Versions 8.0.4/ 8.0.5 and had
the bug no. 690228.
But we use as mentioned 8.1.7.
What do I do wrong?
Any suggestions are welcome.
Thank you
Gerhard

Each raw device you create is used as a single data file.
Eg mklv -y 'myfile' <vgname> <number of logical partitians>
Will have two special files associated with them /dev/rmyfile and /dev/myfile. The number of logical partitians will be the size of your datafile subtract 1 meg for overhead.
So, if you were addding the above raw volume to a tablespace, and the lp size was 32 meg, you would
create tabelspace tsname datafile '/dev/rmyfile' size 31 m;
Note the use of rmyfile not myfile.

Is this a bug in APEX 3.0.1 Installation RAC database with RAW device???

Hello,
I am getting the following error when I try to complete approval process.
ORA-20001: Unable to create tablespace. ORA-01
119: error in creating database file '//./FLOW_1.dbf' ORA-27040: skgfrcre: creat
e error, unable to create file OSD-04002: unable to open file O/S-Error: (OS 2)
The system cannot find the file specified.
I checked the alert log for error here is the error in the alert log file.
ORA-1119 signalled during: CREATE TABLESPACE FLOW_1 DATAFILE '//./FLOW_1.dbf'..
and i found the syntax for create tablespace was wrong.
To create a tablespace in RAC with RAW device environment under windows.
it should have forward black slash instead of backward slash "/" without .dbf extension.
so, I changed the syntax i was able to create tablespace through sqlplus.
When APEX tool try to create this tablespace it throws this error..
Old: CREATE TABLESPACE FLOW_1 DATAFILE
'\\.\FLOW_1.dbf' SIZE 10304 K REUSE AUTOEXTEND OFF
EXTENT MANAGEMENT LOCAL AUTOALLOCATE SEGMENT SPACE MANAGEMENT AUTO
error : ORA-01119: error in creating database file '\\.\FLOW_1.dbf'
New:
CREATE TABLESPACE FLOW_1 DATAFILE
'\\.\FLOW_1' SIZE 10304 K REUSE AUTOEXTEND OFF
EXTENT MANAGEMENT LOCAL AUTOALLOCATE SEGMENT SPACE MANAGEMENT AUTO
Tablespace created.
Is it a bug in APEX 3.0.1.??
Is anyone installed APEX in RAC ??
James

Hi,
One observation, Apex is switching the Session ID after one got killed ? I was working on Apex page with browse Item to test open cursor count,
after killing the SID (227) on which the open cursor count was getting increase, it APEX automatically switches to new SID(149) for that session.
Now the problem is even if I have two SID's and one hits the maximum open cursor count, It is not switching to other SID instead the whole application becomes unavailable.
STATNAME SID VALUE USER
opened cursors current 20 14 APEX_PUBLIC_USER
opened cursors current 149 74 APEX_PUBLIC_USER
opened cursors current 194 71 APEX_PUBLIC_USER
opened cursors current 211 5 APEX_PUBLIC_USER
opened cursors current 227 325 APEX_PUBLIC_USER Killed
opened cursors current 244 15 APEX_PUBLIC_USER
opened cursors current 20 14 APEX_PUBLIC_USER
opened cursors current 149 76 APEX_PUBLIC_USER
opened cursors current 194 71 APEX_PUBLIC_USER
opened cursors current 211 5 APEX_PUBLIC_USER
opened cursors current 244 15 APEX_PUBLIC_USER
Please kindly help in this.
Thanks in Advance
Thanks & Regards
Sanjay
Edited by: user11204334 on Dec 8, 2010 1:02 AM

How to setup the raw devices permissions permanantly in 11gr2 on RHEL 5.

Hi All,
Succesfully installed 11gr2 RAC and working fine , but in next boot raw devices permissions revert back to root .
Please advice me to how to setup permissions permanantly as the oracle user.
Regards
San
.

you find the lib on this page:
http://www.oracle.com/technetwork/topics/linux/downloads/rhel5-084877.html
in the AMD64 / Intel em64t Architecture table
this is the direct link
http://oss.oracle.com/projects/oracleasm/dist/files/RPMS/rhel5/amd64/2.0.5/2.6.18-194.el5/oracleasm-2.6.18-194.el5xen-2.0.5-1.el5.x86_64.rpm
hth
p.s. don't forget to mark question as helpful/correct and close the question.

Content Server 6.40 on Raw Devices

Hi Folks!
We'd like to install a Content Server 6.40 using raw devices (on Linux Suse SLES9).
Do we need to install the MaxDB, if we use raw devices? At this point the InstGuide does not give a clear description of what to do. It looks we can use the raw devices directly without having a database instance. Is this right?
Is there any disadvantage compared to using the access via file system and DB?
Any hint is appreciated...
Best regards
Torsten

Hi Torsten,
As far as i know SAP Content Server use MaxDB or a File System, I have use it with MaxDB with good results, anyhow.... read the following for details,
http://help.sap.com/saphelp_nw04s/helpdata/en/40/32104211625933e10000000a155106/content.htm
Regards
Juan
Please reward with points if helpdul

Raw devices files

Similar Messages

Maybe you are looking for