Dirk-Jan's blog

Oracle 11g ASM disk discovery

Dirk-Jan — Fri, 20 Jan 2012 15:49:57 +0000

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  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!

Zimbra and webOS

Dirk-Jan — Thu, 19 Jan 2012 14:26:51 +0000

I would like to share my experience with webOS in combination with Zimbra Collaboration Suite. For the past two years I’m using Zimbra Open Source edition and I am pretty satisfied with it. It handles my email, contacts, calendar and tasks very well. Call me paranoid, but I don’t like Google or Yahoo! to watch over my personal data. All was working well till I received my first webOS device, an HP TouchPad, which I wanted to connect to my Zimbra server to manage email, appointments, contacts and tasks. Doing some searches I discovered it is possible to use Exchange (ActiveSync) with Zimbra Mobile, but I had the wrong edition of Zimbra. It appeared Zimbra Mobile is available for all Zimbra editions except for the Open Source edition I was using, that’s how they earn their money. I chose to go for the Zimbra Appliance Basic Free Edition. This free edition allows you to create up to 10 mailboxes, which is enough for myself and some family members.

I am using VirtualBox virtualization software, which works with the VMDK from the ZCA zip file. The configuration and migration from one Zimbra edition to the other went relatively smooth. The first thing to test was to setup my HP TouchPad and HP Pre3 smartphone (both collectors items now) and both are connected without a glitch.

One last catch, be careful with the Zimbra default mobile policy. Remote wipe works extremely well if you enter four incorrect your pin codes.

After all I am pretty pleased the way it’s working.

My specs:

VirtualBox 4.1 on Debian 5 (Lenny)
ZCA 6.0.13 (Installed) upgraded to 6.0.14 (6.0.15 is on it’s way to be released shortly)
HP TouchPad 3.0.5
HP Pre3 2.2.4

Server upgrade

Dirk-Jan — Sun, 15 Jan 2012 17:54:15 +0000

This week I decided it was time to upgrade my home server. The main reasons, lack of 64-bit support and virtualization technology (VT-x) in my existing setup. The performance gain was also a nice side effect. I have come up with the following new components:

Intel DQ67EPB3, S1155, Q67, 2xDDR3, mITX
Intel Core i3-2120T, 2.60GHz, 3MB, HD2000, S1155
Kingston ValueRam 8GB(2x4GB) DDR3 1333MHz CL9

The Intel motherboard claims to be energy efficient and the i3 processor has a max thermal design power (TDP) of 35W. I think this is a nice balanced setup to do low-end virtualization with low-power consumption in mind. I might do a power consumption measurement one day.

Once all was installed and the new system booted it appeared networking did not come up in Debian 5 (Lenny).

I had to download and build the driver manually, see the instructions below:

lspci showed: Ethernet controller: Intel Corporation Device 1502 (rev 04)

Look for the “Intel® 82579 Gigabit Ethernet Controller” on the http://downloadcenter.intel.com website.

tar xvzf e1000e-1.9.5.tar.gz
cd e1000e-1.9.5/src
make install
modprobe e1000e
ifconfig eth0 up

Search safely with ixquick

Dirk-Jan — Thu, 15 Sep 2011 21:11:29 +0000

Ixquick claims to be the only search engine that does not record your IP address. According to Wikipedia, “Ixquick is a metasearch engine based in New York and the Netherlands, and has provided over 120 million searches since 2004.”, but even more interestingly “Ixquick.com became the first search engine to delete private details of its users. IP addresses and other personal information are deleted within 48 hours of a search.
Ixquick also does not share its users’ personal information with other search engines or with the provider of its sponsored results. As of January 29th 2009 Ixquick no longer records users’ IP addresses at all.”
Even better, it’s also available via https, which means your ISP, or your employer cannot normally track what you are searching.

I’ve just added it to my browsers default search bar and it does it’s job quite well, so I thought let’s share. Give it a try yourself!

HP TouchPad is here to stay

Dirk-Jan — Sat, 06 Aug 2011 21:31:33 +0000

Today I have received my HP TouchPad I have waited for. This is a new tablet from HP with the same form factor as the well known iPad. The greatest difference between them is the operating system. HP acquired Palm for it’s advanced webOS. With features like true multitasking, non interrupting notifications, intuitive navigation and work flow and a lot more.

In the short amount of time I have spend getting to know the TouchPad make me realize I’m already quite accustomed to it.

This post is actually written on the TouchPad using the WordPress app from the HP app store which I’m currently test driving and I like it!

SCOM 2007 and RHEL6

Dirk-Jan — Wed, 20 Jul 2011 15:51:04 +0000

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.

Home server HDD upgrade

Dirk-Jan — Sat, 18 Jun 2011 20:43:50 +0000

It’s been 1,5 year since I build a new home server. I’m quite happy with this system, but lately I am running out of hard disk space. This is mainly caused by HD movie editing which I’m recently into. That’s why I bought two new 2 TB hard disks (WD20EARS) today to replace the current 1 TB ones (WD10EVVS).

I’ve done my hard disk setup with Linux soft raid 1 (mirror). So the plan is to break the mirror switch one pair of disks, rebuild the mirror and repeat this for the other pair.

It essentially comes down to the following commands having two disks, sda and sdb, both with two partitions.

Break the mirror:

# mdadm /dev/md0 --set-faulty /dev/sdb1
mdadm: set /dev/sdb1 faulty in /dev/md0
# mdadm /dev/md0 --remove /dev/sdb1
mdadm: hot removed /dev/sdb1
# mdadm /dev/md1 --set-faulty /dev/sdb2
mdadm: set /dev/sdb2 faulty in /dev/md0
# mdadm /dev/md1 --remove /dev/sdb2
mdadm: hot removed /dev/sdb2

Shutdown the system, and swap disks. Be sure to swap the correct disk, the one that have been removed from the mirror.

Power on the system and partition the newly added disk. This is where I had to pay attention. It appears the new Western Digital disks are 4096-byte per sector disks instead of the traditional 512-byte sector disks. In order to have good performing disks I had to correct the alignment of the new disk. This covered in greater detail on this page.

Partition the disks (ensure that you’re root filesystem is bootable):

Device Boot      Start         End      Blocks   Id  System
/dev/sdb1              64         126      506047+  fd  Linux raid autodetect
/dev/sdb2             134       12292    97667167+  fd  Linux raid autodetect

Add the new disk to the mirror and watch the sync progress:

# mdadm /dev/md0 --add /dev/sdb1
# watch cat /proc/mdstat
# mdadm /dev/md1 --add /dev/sdb2
# watch cat /proc/mdstat

Install grub on the new disk and repeat the above steps for the other disk.

After the sync is completed run the grow command:

# mdadm /dev/md1 --grow --size=max

Finishing steps:

# pvresize --verbose /dev/md0
# lvresize --verbose -L  /dev/mapper/VG-LV
# resize2fs /dev/mapper/VG-LV

VOIP problemo

Dirk-Jan — Fri, 06 May 2011 08:53:35 +0000

Today I encountered a strange problem when I tried making a phone call using my home VOIP telephone. I could dial out, but there was no sound coming through, which is pretty confusing. At first I thought it had something to do with the firmware update I did recently on my Siemens A580 IP. After spending half an hour troubleshooting it appeared to be my VOIP provider uses another sip server to talk back to my Asterisk server. After adding this new server ip to my firewall configuration the sound is coming through again, which is the essence of telephony.

Added firewall rule:

access-list 101 permit udp host 83.143.188.182 host 
access-list 101 permit udp host 83.143.188.186 host

I think this could be useful for other Budgetphone VOIP users experiencing the same.

Terminal not big enhough

Dirk-Jan — Wed, 23 Feb 2011 19:27:00 +0000

Today we recieved a new system to enroll our Linux operating system on. It comes with two six core Intel Xeon processors with hyperthreading enabled. When the installation was finished I fired up top and switched to SMP view, which didn’t worked. It displayed the following message (have a look at the picture). I had to enlarge the terminal to have all 24 cpu’s displayed. Too funny!
Do we get ahead of Moore’s law?

MacBook Pro slowdown

Dirk-Jan — Thu, 04 Nov 2010 19:00:06 +0000

Today my recently acquired MacBook Pro was feeling unresponsive and acting much slower than it used to be and not consuming any noteworthy CPU cycles. Doing some searches on the web it appears to be a common problem with the System Management Controller (SMC). After resetting the SMC it’s performing as expected. Those were the steps I carried out.

Shut down the computer.
Unplug the computer’s power cord.
Press and hold the power button for 5 seconds.
Release the power button.
Attach the computers power cable.
Press the power button to turn on the computer.

Have a look at knowledge base article ht3964 for more information.