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Posts Tagged ‘Red Hat’

Oracle 11g ASM disk discovery

January 20th, 2012 No comments

During the installation of Oracle 11gR2 on Red Hat Enterprise Linux 5 I stumbled upon a incorrect default setting for ASM disk discovery when using ASM lib. The discovery path is set to ‘/dev/raw/sd*’, which is incorrect because ASM lib creates the devices under ‘/dev/oracleasm/disks’.

Another thing to be aware of is the ownership of the disks. You need to run ‘/etc/init.d/oracleasm configure’ in order to configure the owner. If you just hit return the ownership of the disks is set to root. Because you will start the Oracle installation as user oracle the disks will not appear in the discovery step during the installation.

Incorrect ownership:

# ls -l /dev/oracleasm/disks/*
brw------- 1 root root 8, 65 Jan 20 15:27 /dev/oracleasm/disks/VOL1
brw------- 1 root root 8, 49 Jan 20 15:27 /dev/oracleasm/disks/VOL2
brw------- 1 root root 8, 33 Jan 20 15:27 /dev/oracleasm/disks/VOL3

Configure Oracle ASM Library:

# /etc/init.d/oracleasm configure
Configuring the Oracle ASM library driver.

This will configure the on-boot properties of the Oracle ASM library
driver.  The following questions will determine whether the driver is
loaded on boot and what permissions it will have.  The current values
will be shown in brackets ('[]').  Hitting <ENTER> without typing an
answer will keep that current value.  Ctrl-C will abort.

Default user to own the driver interface []: oracle
Default group to own the driver interface []: oinstall
Start Oracle ASM library driver on boot (y/n) [y]:
Scan for Oracle ASM disks on boot (y/n) [y]:
Writing Oracle ASM library driver configuration: done
Initializing the Oracle ASMLib driver:                     [  OK  ]
Scanning the system for Oracle ASMLib disks:               [  OK  ]

Correct ownership:

# ls -l /dev/oracleasm/disks/
total 0
brw-rw---- 1 oracle oinstall 8, 33 Jan 20 15:27 VOL1
brw-rw---- 1 oracle oinstall 8, 49 Jan 20 15:27 VOL2
brw-rw---- 1 oracle oinstall 8, 65 Jan 20 15:27 VOL3
[root@porad001 ~]#

Hope it saves you some time!

Categories: Oracle Tags: ,

SCOM 2007 and RHEL6

July 20th, 2011 No comments

Cumulative Update 5 for System Center Operations Manager 2007 R2 brings support for Red Hat 6. This update is release on August 4, 2011. Red Hat Enterprise Linux 6 was release on November 10, 2010. So Microsoft managed to put out an update with support for RHEL6 9 months later. This new management pack is not included in the update, you have to download en and import it separately.

Categories: Linux Tags: ,

Install SCOM agent on Red Hat Linux

March 3rd, 2010 4 comments

The steps below describe how to install the SCOM agent on Red Hat Linux 5 x64. We don’t like to enroll the agent by using the SCOM Discovery wizard, as you need to enter the super-user (root)credentials and we’re not sure where the application stores those credentials and it’s used for. So we’re still searching for the minimal permissions for the agent to be installed.

It is possile to install the agent, copy the unsigned client-side generated certificate to the SCOM server, sign the certificate on the SCOM server and copy the signed certificate back to the client. Once you have restarted the scx daemon you can use the discovery wizard on the SCOM server to add the server without using super-user credentials in SCOM.

Once you have installed the Cross Platform Cumulative Update 2 for System Center Operations Manager 2007 R2, a newer version of the agent becomes available on the SCOM server in Program Files\System Center Operations Manager 2007\AgentManagement\UnixAgents.


# rpm -ivh scx-1.0.4-258.rhel.5.x64.rpm
Preparing...                ########################################### [100%]
   1:scx                    ########################################### [100%]
Generating certificate with hostname="host001", domainname="example.local"

WARNING!
Could not read 256 bytes of random data from /dev/random. Will revert to less secure /dev/urandom.
See the security guide for how to regenerate certificates at a later time when more random data might be available.

/var/tmp/rpm-tmp.63356: line 163: /usr/lib/lsb/install_initd: No such file or directory
Starting Microsoft SCX CIM Server: [  OK  ]
#

To fix the above problem you can use the following work-around.

rm /dev/random
rm: remove character special file `/dev/random'? y
# mknod -m 644 /dev/random c 1 9
# chown root:root /dev/random
# cd
# rpm -ivh scx-1.0.4-258.rhel.5.x64.rpm
Preparing...                ########################################### [100%]
   1:scx                    ########################################### [100%]
Generating certificate with hostname="host001", domainname="example.local"
/var/tmp/rpm-tmp.10879: line 163: /usr/lib/lsb/install_initd: No such file or directory
Starting Microsoft SCX CIM Server: [  OK  ]
# rm /dev/random
# mknod -m 644 /dev/random c 1 8
# chown root:root /dev/random


Categories: Linux Tags: , ,