Cloud Services | Exadata | Linux – Page 13

Database, Errors and Bugs, Linux, Migration | Upgrades | Patching

ORA-27302: failure occurred at: sskgpcreates

By matheusdba 9 de July de 2015 21 de April de 2020

# Error:

dbsrvr1:/home/oracle>srvctl start database -d mydb
PRCR-1079 : Failed to start resource ora.mydb.db
CRS-5017: The resource action "ora.mydb.db start" encountered the following error:
ORA-27154: post/wait create failed
ORA-27300: OS system dependent operation:semget failed with status: 28
ORA-27301: OS failure message: No space left on device
ORA-27302: failure occurred at: sskgpcreates
. For details refer to "(:CLSN00107:)" in "/grid/product/11.2.0.4/log/dbsrvr2/agent/crsd/oraagent_oracle/oraagent_oracle.log".
CRS-2674: Start of 'ora.mydb.db' on 'dbsrvr2' failed
CRS-2632: There are no more servers to try to place resource 'ora.mydb.db' on that would satisfy its placement policy

Seems the weeror is happening on dbsrvr2, right?
The doc below talks more about the error and the semaphores calculation:
Database Startup Fails with ORA-27300: OS system dependent operation:semget failed with status: 28 (Doc ID 949468.1)

Let’s make an adjust here:

[root@dbsrvr2 ~]# cat /etc/sysctl.conf |grep sem
kernel.sem = 250 32000 100 142
[root@dbsrvr2 ~]# vi /etc/sysctl.conf
[root@dbsrvr2 ~]# cat /etc/sysctl.conf |grep sem
kernel.sem = 250 32000 100 256
[root@dbsrvr2 ~]# sysctl -p

And try again:

dbsrvr1:/home/oracle>srvctl start database -d mydb
dbsrvr1:/home/oracle>

Well done! 😀

Matheus.

Database, Errors and Bugs, Windows

Windows: “ORA-12514” After Database Migration/Moving (Using DNS Alias)

By matheusdba 6 de July de 2015 21 de April de 2020

It’s usual to use DNS Aliases pointing to scanlistener. This way, we create an abstraction/layer bewteen clients/application and the cluster where database is. Some activities like tierization/consolidation and database moving between clusters (converting to Pluggable, etc), would be much more transparent.

Buuuut, if after a database migration, all the services online and listening, your client is stucking with:

ORA-12514: TNS:listener does not currently know of service requested in connect descriptor

Remmember you are using DNS to make this layer. Have you tried to flush DNS Cache?
I faced this problem with a Windows Application. The solution:

C:\Users\matheus_boesing>ipconfig /flushdns
Windows IP Configuration
Successfully flushed the DNS Resolver Cache.

All working fine after that. 🙂

Matheus.

ASM, Database, Enterprise Manager, SQL | PLSQL

ASM: Disk Size Imbalance Query

By matheusdba 1 de July de 2015 21 de April de 2020

It can be useful if you work frequently with OEM metrics…

# OEM’s Query

SELECT file_num, MAX(extent_count) max_disk_extents, MIN(extent_count)
min_disk_extents
, MAX(extent_count) - MIN(extent_count) disk_extents_imbalance
FROM (SELECT number_kffxp file_num, disk_kffxp disk_num, COUNT(xnum_kffxp)
extent_count
FROM x$kffxp
WHERE group_kffxp = 1
AND disk_kffxp != 65534
GROUP BY number_kffxp, disk_kffxp
ORDER BY number_kffxp, disk_kffxp)
GROUP BY file_num
HAVING MAX(extent_count) - MIN(extent_count) > 5
ORDER BY disk_extents_imbalance DESC;

# Matheus’ Query

select max(free_mb) biggest, min(free_mb) lowest, avg(free_mb) AVG,
trunc(GREATEST ((avg(free_mb)*100/max(free_mb)),(min(free_mb)*100/avg(free_mb))),2)||'%' as balanced,
trunc(100-(GREATEST ((avg(free_mb)*100/max(free_mb)),(min(free_mb)*100/avg(free_mb)))),2)||'%' as inbalanced
from v$asm_disk
where group_number in
(select group_number from v$asm_diskgroup where name = upper('&DG'));

I made my own query for two reasons:
1) I didn’t have the OEM query in the time i made it.
2) My query measures the imbalance with the avg of the disks (if every disk would balanced, how would be the difference), rather than the real/present difference between the disk with the maximum and the minimum usage…

So, you can chose the one you need… 🙂

Matheus.

Database, Errors and Bugs, Linux

OUI: RHEL Permission Denied error

By matheusdba 30 de June de 2015 21 de April de 2020

Another quick tip about running DBCA:

# Error:

[oracle@dbsrv database]$ ./runInstaller
Starting Oracle Universal Installer...
Checking installer requirements...
All installer requirements met.
Preparing to launch Oracle Universal Installer from /tmp/OraInstall2015-06-25_06-37-23PM. Please wait ...Error in CreateOUIProcess(): 13
: Permission denied

# Solution:

mount -t ext3 -o remount default /tmp

Ok doke?

Matheus.

Database, Errors and Bugs, Linux

RHEL5: Database 10g Installation – Checking operating system version error

By matheusdba 29 de June de 2015 21 de April de 2020

Everything is old. RHEL and Database versions. But can be useful if you are preparing a nonprod lab of your legacy env, right?

Let’s see the problem:

[oracle@dbsrv database]$ ./runInstaller
Starting Oracle Universal Installer...
Checking installer requirements...
Checking operating system version: must be redhat-3, SuSE-9, redhat-4, UnitedLinux-1.0, asianux-1 or asianux-2
Failed <<<<

The “easiest” workaround:

[oracle@dbsrv database]$ ./runInstaller -ignoreSysPrereqs

The “hardway” workaround:

1. Copy parameter file:
$ cp database/install/oraparam.ini /tmp
2. Edit parameter file:
$ vi /tmp/oraparam.ini
2.1. Change
[Certified Versions]
Linux=redhat-3,SuSE-9,redhat-4,UnitedLinux-1.0,asianux-1,asianux-2
to
[Certified Versions]
Linux=redhat-3,SuSE-9,redhat-4,UnitedLinux-1.0,asianux-1,asianux-2,redhat-5
3. Run the installer again:
$ ./runInstaller -paramFile /tmp/oraparam.ini

KB: Requirements For Installing Oracle10gR2 On RHEL 5/OEL 5 (x86_64) [ID 421308.1]

Matheus.

Linux

RHEL: Adding User/Group to SSH and SUDOERS file

By matheusdba 23 de June de 2015 21 de April de 2020

Some Linux basics… To add a group or a user (this case “new_group”) to the ssh and sudoers file:

[root@db-server ~]# vi /etc/ssh/sshd_config
[root@db-server ~]# cat /etc/ssh/sshd_config |grep new_group
AllowGroups ssh_group1 root oinstall linux new_group
[root@db-server ~]# vi /etc/sudoers
[root@db-server ~]# cat /etc/sudoers |grep new_group
%new_group      ALL=(ALL)       PASSWD: ALL
[root@db-server ~]# service sshd restart
Stopping sshd:                                             [  OK  ]
Starting sshd:                                             [  OK  ]
[root@db-server ~]#

Matheus.

Database, Errors and Bugs, Linux

ORA-00845: MEMORY_TARGET not supported on this system (RHEL)

By matheusdba 22 de June de 2015 21 de April de 2020

# Solution:
Make sure that /dev/shm is mounted. You can check this by typing df -k at the command prompt. It will look something like this:

Filesystem Size Used Avail Use% Mounted on
…
shmfs 1G 512M 512M 50% /dev/shm

If you don’t find it then you will have to manually mount it as root user. The size should be more than MEMORY_TARGET or MEMORY_MAX_TARGET.

For example, if the MEMORY_TARGET is less than 2 GB, you should make like that:

#root: mount -t tmpfs shmfs -o size=2048m /dev/shm

I recommend you add an entry in /etc/fstab so that the mount remains persistent even after a reboot.
To make it, add the following entry in /etc/fstab:

shmfs /dev/shm tmpfs size=2048m 0 0

Helped?
Share this post!

Matheus.

ASM, Database, Errors and Bugs, Linux, Shell Scripts

Error: Starting ACFS in RHEL 6 (Can’t exec “/usr/bin/lsb_release”)

By matheusdba 19 de June de 2015 21 de April de 2020

Quick tip:

# Error:
[root@db1gridserver1 bin]# ./acfsload start -s
Can’t exec “/usr/bin/lsb_release”: No such file or directory at /grid/product/11.2.0/lib/osds_acfslib.pm line 511.
Use of uninitialized value $LSB_RELEASE in split at /grid/product/11.2.0/lib/osds_acfslib.pm line 516.

# Solution:
[root@db1gridserver1 bin]# yum install redhat-lsb-core-4.0

Note: Bug 17359415 – Linux: Configuring ACFS reports that cannot execute ‘/usr/bin/lsb_release’ (Doc ID 17359415.8)

Matheus.

ASM, Database, Linux, SQL | PLSQL

Adding ASM Disks on RHEL Cluster with Failgroups

By matheusdba 15 de June de 2015 21 de April de 2020

# Recognizing as ASMDISK on ASM Libs (ORACLEASM):

1) All cluster nodes: /etc/init.d/oracleasm scandisk
[root@db1host1p ~]# /etc/init.d/oracleasm scandisks Scanning the system for Oracle ASMLib disks: [ OK ] [root@db2host2p ~]# /etc/init.d/oracleasm scandisks Scanning the system for Oracle ASMLib disks: [ OK ]

2) One of cluster nodes:
[root@db1host1p ~]# /etc/init.d/oracleasm createdisk DGDATA059 /dev/asmdsk/DGDATA059 Marking disk "DGDATA059" as an ASM disk: [ OK ] [root@db1host1p ~]# /etc/init.d/oracleasm createdisk DGDATA060 /dev/asmdsk/DGDATA060 Marking disk "DGDATA060" as an ASM disk: [ OK ] [root@db1host1p ~]# /etc/init.d/oracleasm createdisk DGDATA061 /dev/asmdsk/DGDATA061 Marking disk "DGDATA061" as an ASM disk: [ OK ] [root@db1host1p ~]# /etc/init.d/oracleasm createdisk DGDATA062 /dev/asmdsk/DGDATA062 Marking disk "DGDATA062" as an ASM disk: [ OK ] [root@db1host1p ~]# /etc/init.d/oracleasm createdisk DGDATA159 /dev/asmdsk/DGDATA159 Marking disk "DGDATA159" as an ASM disk: [ OK ] [root@db1host1p ~]# /etc/init.d/oracleasm createdisk DGDATA160 /dev/asmdsk/DGDATA160 Marking disk "DGDATA160" as an ASM disk: [ OK ] [root@db1host1p ~]# /etc/init.d/oracleasm createdisk DGDATA161 /dev/asmdsk/DGDATA161 Marking disk "DGDATA161" as an ASM disk: [ OK ] [root@db1host1p ~]# /etc/init.d/oracleasm createdisk DGDATA162 /dev/asmdsk/DGDATA162 Marking disk "DGDATA162" as an ASM disk: [ OK ]

3) All cluster nodes: /etc/init.d/oracleasm scandisk
[root@db1host1p ~]# /etc/init.d/oracleasm scandisks Scanning the system for Oracle ASMLib disks: [ OK ] [root@db2host2p ~]# /etc/init.d/oracleasm scandisks Scanning the system for Oracle ASMLib disks: [ OK ]

# Adding Disk on Diskgroup (sqlplus / as sysasm – ASM Instance)
1) Listing Failgroups
SQL> select distinct failgroup from v$asm_disk where group_number in (select group_number from v$asm_diskgroup where name='DGDATA'); FAILGROUP ---------------------------------------------------- FGMASTER FGAUX

1) Adding Disks (naming and setting rebalance power):
SQL> alter diskgroup DGDATA 2 add failgroup FG01 disk 3 'ORCL:DGDATA059' name DGDATA059, 4 'ORCL:DGDATA060' name DGDATA060, 5 'ORCL:DGDATA061' name DGDATA061, 6 'ORCL:DGDATA062' name DGDATA062 7 add failgroup FG02 disk 8 'ORCL:DGDATA159' name DGDATA159, 9 'ORCL:DGDATA160' name DGDATA160, 10 'ORCL:DGDATA161' name DGDATA161, 11 'ORCL:DGDATA162' name DGDATA162 12 rebalance power 10 nowait; Diskgroup altered

2) Be patient, and wait the rebalancing:
SQL> select * from v$asm_operation; GROUP_NUMBER OPERATION STATE POWER ACTUAL SOFAR EST_WORK EST_RATE EST_MINUTES ERROR_CODE ------------ ----------- ---------- ---------- ---------- ----------- 4 REBAL RUN 10 10 191386 540431 1651 211 5 REBAL WAIT 4 SQL> / GROUP_NUMBER OPERATION STATE POWER ACTUAL SOFAR EST_WORK EST_RATE EST_MINUTES ERROR_CODE ------------ --------------- ---------------------------------------- 4 REBAL RUN 10 10 443438 548118 2345 44 5 REBAL WAIT 4 SQL> / no rows selected

Well done! 😀
Matheus.

ASM, Database, Linux, Shell Scripts

Manually Mounting ACFS

By matheusdba 12 de June de 2015 21 de April de 2020

A server rebooted and I needed to remount the ACFS where the Oracle Home is. About that:
Today’s post: Manually Mounting ACFS
~~Tomorrow’s~~ Someday’s post: Kludge: Mounting ACFS Thought Shellscript
~~Day Before Tomorrow’s~~ ~~Another~~ Day’s post: Auto Mounting Cluster Services Through Oracle Restart

But, first, some usefull links:
– ACFS Introduction
– ACFS Advanced
– ACFS Command-Line Utilities

# Manually Mounting ACFS
Checked my $ORACLE_HOME (mounted on ACFS) is not available to start the database. Checked ACFS service is down. So, let’s do all the process:

# Starting ACFS
[root@db1host1p ~]$ $GRID_HOME/bin/acfsload start -s

# Volumes OFFLINE: Let’s Enable it:
[root@db1host1p ~]$ $GRID_HOME/bin/crsctl stat res -t |grep acfs ora.dghome.sephome.acfs ONLINE OFFLINE db1host1p [root@db1host1p ~]$ su - grid [grid@db1host1p ~]$ asmcmd ASMCMD> volinfo -a Diskgroup Name: DGHOME Volume Name: LVHOME Volume Device: /dev/asm/lvhome-270 State: DISABLED Size (MB): 10240 Resize Unit (MB): 32 Redundancy: MIRROR Stripe Columns: 4 Stripe Width (K): 128 Usage: ACFS Mountpath: /oracle/MYDB ASMCMD> volenable -a ASMCMD> volinfo -a Diskgroup Name: DGHOME Volume Name: LVHOME Volume Device: /dev/asm/lvhome-270 State: ENABLED Size (MB): 10240 Resize Unit (MB): 32 Redundancy: MIRROR Stripe Columns: 4 Stripe Width (K): 128 Usage: ACFS Mountpath: /oracle/MYDB

[root@db1host1p ~]$ $GRID_HOME/bin/crsctl stat res -t |grep acfs ora.dghome.sephome.acfs ONLINE ONLINE db1host1p mounted on /oracle/MYDB ONLINE ONLINE db2host2p mounted on /oracle/MYDB

# As root, let’s mount it:
[root@db1host1p ~]# mount -t acfs /dev/asm/lvhome-270 /oracle/MYDB

# Then, with the $ORACLE_HOME available:
[oracle@db1host1p ~]$ srvctl start instance -d MYDB -i MYDB001

Matheus.