################################################################
# Adding/Removing/Managing ASM instances
################################################################

--Use the following syntax to add configuration information about an existing ASM instance:
 srvctl add asm -n node_name -i +asm_instance_name -o oracle_home

--Use the following syntax to remove an ASM instance:
 srvctl remove asm -n node_name [-i +asm_instance_name]

--Use the following syntax to enable an ASM instance:
 srvctl enable asm -n node_name [-i ] +asm_instance_name

--Use the following syntax to disable an ASM instance:
 srvctl disable asm -n node_name [-i +asm_instance_name]

--Use the following syntax to start an ASM instance:
 srvctl start asm -n node_name [-i +asm_instance_name] [-o start_options]

--Use the following syntax to stop an ASM instance:
 srvctl stop asm -n node_name [-i +asm_instance_name] [-o stop_options]

--Use the following syntax to show the configuration of an ASM instance:
 srvctl config asm -n node_name

--Use the following syntax to obtain the status of an ASM instance:
 srvctl status asm -n node_name

P.S.:

For all of the SRVCTL commands in this section for which an option is not required, if the instance name “-i” is not specified the command applies  to all ASM instances.

 

###################################
# Managing DiskGroup inside ASM:
###################################

–Note that adding or dropping disks will initiate a rebalance of the data on the disks.
–The status of these processes can be shown by selecting from v$asm_operation.

--Quering ASM Disk Groups
 col name format a25
 col DATABASE_COMPATIBILITY format a10
 col COMPATIBILITY format a10
 select * from v$asm_diskgroup;
 --or
 select name, state, type, total_mb, free_mb from v$asm_diskgroup;

--Quering ASM Disks
 col PATH format a55
 col name format a25
 select name, path, group_number, TOTAL_MB, FREE_MB, READS, WRITES, READ_TIME,
 WRITE_TIME from v$asm_disk order by 3,1;
 --or
 col PATH format a50
 col HEADER_STATUS  format a12
 col name format a25
 --select INCARNATION,
 select name, path, MOUNT_STATUS,HEADER_STATUS, MODE_STATUS, STATE, group_number,
 OS_MB, TOTAL_MB, FREE_MB, READS, WRITES, READ_TIME, WRITE_TIME, BYTES_READ,
 BYTES_WRITTEN, REPAIR_TIMER, MOUNT_DATE, CREATE_DATE from v$asm_disk;

 

 

################################################################
# Tuning and Analysis
################################################################

–Performance Statistics

–N.B Time in Hundred seconds!

 col READ_TIME format 9999999999.99
 col WRITE_TIME format 9999999999.99
 col BYTES_READ format 99999999999999.99
 col BYTES_WRITTEN  format 99999999999999.99
 select name, STATE, group_number, TOTAL_MB, FREE_MB,READS, WRITES, READ_TIME,
 WRITE_TIME, BYTES_READ, BYTES_WRITTEN, REPAIR_TIMER,MOUNT_DATE
 from v$asm_disk order by group_number, name;

 

--Check the Num of Extents in use per Disk inside one Disk Group.
 select max(substr(name,1,30)) group_name, count(PXN_KFFXP) extents_per_disk,
 DISK_KFFXP, GROUP_KFFXP from x$kffxp, v$ASM_DISKGROUP gr
 where GROUP_KFFXP=&group_nr and GROUP_KFFXP=GROUP_NUMBER
 group by GROUP_KFFXP, DISK_KFFXP order by GROUP_KFFXP, DISK_KFFXP;

--Find The File distribution Between Disks
 SELECT * FROM v$asm_alias  WHERE  name='PWX_DATA.272.669293645';

SELECT GROUP_KFFXP Group#,DISK_KFFXP Disk#,AU_KFFXP AU#,XNUM_KFFXP Extent#
 FROM   X$KFFXP WHERE  number_kffxp=(SELECT file_number FROM v$asm_alias
 WHERE name='PWX_DATA.272.669293645');

--or

SELECT GROUP_KFFXP Group#,DISK_KFFXP Disk#,AU_KFFXP AU#,XNUM_KFFXP Extent#
 FROM X$KFFXP WHERE  number_kffxp=&DataFile_Number;

--or
 select d.name, XV.GROUP_KFFXP Group#, XV.DISK_KFFXP Disk#,
 XV.NUMBER_KFFXP File_Number, XV.AU_KFFXP AU#, XV.XNUM_KFFXP Extent#,
 XV.ADDR, XV.INDX, XV.INST_ID, XV.COMPOUND_KFFXP, XV.INCARN_KFFXP,
 XV.PXN_KFFXP, XV.XNUM_KFFXP,XV.LXN_KFFXP, XV.FLAGS_KFFXP,
 XV.CHK_KFFXP, XV.SIZE_KFFXP from v$asm_disk d, X$KFFXP XV
 where d.GROUP_NUMBER=XV.GROUP_KFFXP and d.DISK_NUMBER=XV.DISK_KFFXP
 and number_kffxp=&File_NUM order by 2,3,4;

--List the hierarchical tree of files stored in the diskgroup
 SELECT concat('+'||gname, sys_connect_by_path(aname, '/')) full_alias_path FROM
 (SELECT g.name gname, a.parent_index pindex, a.name aname,
 a.reference_index rindex FROM v$asm_alias a, v$asm_diskgroup g
 WHERE a.group_number = g.group_number)
 START WITH (mod(pindex, power(2, 24))) = 0
 CONNECT BY PRIOR rindex = pindex;

 

 

###################################
#Create and Modify Disk Group
###################################

create diskgroup FRA1 external redundancy disk '/dev/vx/rdsk/oraASMdg/fra1'
 ATTRIBUTE 'compatible.rdbms' = '11.1', 'compatible.asm' = '11.1';

alter diskgroup FRA1  check all;

--on +ASM2 :
 alter diskgroup FRA1 mount;

--Add a second disk:
 alter diskgroup FRA1 add disk '/dev/vx/rdsk/oraASMdg/fra2';

--Add several disks with a wildcard:
 alter diskgroup FRA1 add disk '/dev/vx/rdsk/oraASMdg/fra*';

--Remove a disk from a diskgroup:
 alter diskgroup FRA1 drop disk 'FRA1_0002';

--Drop the entire DiskGroup
 drop diskgroup DATA1 including contents;

--How to DROP the entire DiskGroup when it is in NOMOUNT Status
 --Generate the dd command which will reset the header of all the
 --disks belong the GROUP_NUMBER=0!!!!
 select 'dd if=/dev/zero of=''' ||PATH||''' bs=8192 count=100' from v$asm_disk
 where GROUP_NUMBER=0;

select * from v$asm_operation;

————————————————————————–

alter diskgroup FRA1 drop disk 'FRA1_0002';
 alter diskgroup FRA1 add disk '/dev/vx/rdsk/fra1dg/fra3';

alter diskgroup FRA1 drop disk 'FRA1_0003';
 alter diskgroup FRA1 add disk '/dev/vx/rdsk/fra1dg/fra4';

 

When a new diskgroup is created, it is only mounted on the local instance,
and only the instance-specific entry for the asm_diskgroups parameter is updated.
By manually mounting the diskgroup on other instances, the asm_diskgroups parameter on those instances are updated.

--on +ASM1 :
 create diskgroup FRA1 external redundancy disk '/dev/vx/rdsk/fradg/fra1'
 ATTRIBUTE 'compatible.rdbms' = '11.1', 'compatible.asm' = '11.1';

--on +ASM2 :
 alter diskgroup FRA1 mount;

--It works even for on going balances!!!
 alter diskgroup DATA1 rebalance power 10;

 

################################################################
# New ASM Command Line Utility (ASMCMD) Commands and Options
################################################################

ASMCMD Command Reference:

Command Description
 --------------------
 - cd Command Changes the current directory to the specified directory.
 - cp Command Enables you to copy files between ASM disk groups on a local instance and remote instances.
 - du Command Displays the total disk space occupied by ASM files in the specified
 - ASM directory and all of its subdirectories, recursively.
 - exit Command Exits ASMCMD.
 - find Command Lists the paths of all occurrences of the specified name (with wildcards) under the specified directory.
 - help Command Displays the syntax and description of ASMCMD commands.
 - ls Command Lists the contents of an ASM directory, the attributes of the specified
 - file, or the names and attributes of all disk groups.
 - lsct Command Lists information about current ASM clients.
 - lsdg Command Lists all disk groups and their attributes.
 - lsdsk Command Lists disks visible to ASM.
 - md_backup Command Creates a backup of all of the mounted disk groups.
 - md_restore Command Restores disk groups from a backup.
 - mkalias Command Creates an alias for system-generated filenames.
 - mkdir Command Creates ASM directories.
 - pwd Command Displays the path of the current ASM directory.
 - remap Command Repairs a range of physical blocks on a disk.
 - rm Command Deletes the specified ASM files or directories.
 - rmalias Command Deletes the specified alias, retaining the file that the alias points to.

--------
 -- kfed tool From Unix Prompt for reading ASM disk header.
 kfed read /dev/vx/rdsk/fra1dg/fra1

 

################################################################
# CREATE and Manage Tablespaces and Datafiles on ASM
################################################################

CREATE TABLESPACE my_ts DATAFILE '+disk_group_1' SIZE 100M AUTOEXTEND ON;

ALTER TABLESPACE sysaux ADD DATAFILE '+disk_group_1' SIZE 100M;

ALTER DATABASE DATAFILE '+DATA1/dbname/datafile/audit.259.668957419' RESIZE 150M;

-------------------------
 create diskgroup DATA1 external redundancy disk '/dev/vx/rdsk/oraASMdg/fra1'
 ATTRIBUTE 'compatible.rdbms' = '11.1', 'compatible.asm' = '11.1';

select 'alter diskgroup DATA1 add disk ''' || PATH || ''';' from v$asm_disk
 where GROUP_NUMBER=0 and rownum<=&Num_Disks_to_add;

select 'alter diskgroup FRA1 add disk ''' || PATH || ''';' from v$asm_disk
 where GROUP_NUMBER=0 and rownum<=&Num_Disks_to_add;

--Remove ASM header
 select 'dd if=/dev/zero of=''' ||PATH||''' bs=8192 count=100' from v$asm_disk
 where GROUP_NUMBER=0;