l1dge

Mastering emacs.....again!!!

2011-10-15T06:13:00.001+01:00

This weekend I've decide to have another crack at mastering Emacs. I was trawling through some old bookmarks and files I had on my machine and it renewed my enthusiasm for Emacs by re-reading my friends blog at Mastering Emacs. Please check it out, some really good tutorials for beginners and advanced Emacs users alike.

Places to eat in SF

2011-10-06T18:13:00.000+01:00

SC if you read this, check out the "Mels diner" franchise for some great fast food. Authentic 50's style diner. And for something a bit more sophisticated, I can recommend Morton's steak house, 400 Post Street just off Union Square.
There are also some fantastic restaurants in Japantown, check out the Japan Centre if you get time.

Have a good trip!!!

AWR Slideshows

2011-10-04T00:28:00.000+01:00

Having seen Mike Aults presentation at OpenWorld this morning, I thought I'd share the link to some excellent slideshow presentations he has done on AWR and Tuning.

http://www.slideshare.net/texasmemorysystems/using-awr-for-sql-analysis-8237394

Oracle Openworld Keynote

2011-10-03T01:13:00.001+01:00

What an awesome start to Openworld, some really great sessions so far today. Keynote due to start at 17:30.

On my way to Oracle Open World

2011-09-30T11:13:00.001+01:00

Sitting in the lounge at the airport before the first leg of the journey to San Francisco....sweet!!

Mass renaming Directories from the command shell

2011-07-09T09:46:00.000+01:00

I needed to rename a lot of directories from 'S0?' to 'Season ?' found an easy way of doing this from the command line:

find /media/ -type d -iname 'S0?' -exec renamexm -s/S0/Season\ /g {} \;

A Guide to Efficiently Using Irssi and Screen | quadpoint.org

2011-02-27T09:26:00.000Z

Check out this cool guide to Irssi.

A Guide to Efficiently Using Irssi and Screen | quadpoint.org

Checkpoint Secure Remote

2011-02-26T19:58:00.000Z

To change the mode of Checkpoints Secure Remote so you can do a "Right-click -> Connect" on the icon in systray, run this in a command prompt

cd \Program Files\CheckPoint\SecuRemote\bin
scc.exe setmode con

And this should solve your problem.

MPD and Alsa

2011-02-26T11:24:00.001Z

So after upgrdaing to Arch Linux (an event in itself), I had issues with MPD not being able to talk to the soundcard. In the mpd log I was seeing errors like "Failed to open device HW:0,0" or "Failed to open [Alsa] device". Now after a couple of days of scratching around I suddenly had a light bulb moment, "was the mpd user in the audio group???" I checked and it wasn't, so a quick "sudo vigr" and hey presto I had sound working again.
What threw me during the diagnosis of this, was that running 'speaker-test -c2' from the command line was producing sound so it led me to believe it had to be localised to mpd.

Anyway, that's another problem solved!!

Now I can get back to working on a post on how to configure the Awesome Window manager.

Emacs

2010-11-10T14:27:00.000Z

This is an excellent website for finding out about all things emacs, head on over to masteringemacs.org.

Possibly fix access issue on citrix.

2010-09-16T22:20:00.001+01:00

KBAlertz.com: When you open an Access database, you may receive the following error message: Microsoft Access couldn't find file ' system.mdw '. This file is required for startup Note The name of the file System.mdw may be different. When you run the Workgroup...

Published with Blogger-droid v1.5.9

Security Auditing Matching Up Logins And Users

2010-08-25T09:16:00.000+01:00

Good article on SQL User Auditing

Security Auditing Matching Up Logins And Users

Thanks to OMG Ununtu for this one, fixed my image tearing issue

2010-07-11T12:11:00.000+01:00

How To Fix Video Tearing In Videos; Nvidia, Ubuntu
0diggsdigg
1/25/2010 by d0od
Tags: compiz, nvidia, screentearing, tips, vlc
Screen-tearing is an issue for many Nvidia users on Ubuntu. Videos are plauaged by a visible 'tear' mid way through the screen during any moments of intense action or horizontal panning. Gamers find anything that sidescrolls too much also results in the same issue. Here's an example of it: -

Thankfully kopiwe over on the Ubuntu Forums has posted an amazing tutorial on how to finally get rid of screen tearing in Ubuntu - providing you're using a Nvidia graphics card. I've re-written it here and provided some screenshots for those less confident about changing settings. Please go and thank him in the thread on the forums.
Preparation To fix thread-tearing you're going to need the CompizConfig Settings Manager and Nvidia X Server Settings installed. The later was most likely be installed along with your graphics drivers, the former can be installed using: -

* sudo apt-get install compizconfig-settings-manager

or by searching for Compizconfig in the Ubuntu Software Centre. Step 1

* Open up the CompizConfig Settings manager via the System > Preferences menu
* Click the 'General Options' button and go to the 'Display Settings' tab
* Change the 'refresh rate' to '60' using the slider (though higher if you're a gamer, etc)
* Tick the 'Sync To VBlank' check-box

Step 2

* Open Nvidia X Server Settings Via the System > Preferences Menu
* Choose 'OpenGL Settings' on the left-hand side
* Check the box next to "Sync To VBlank" to enable it

Step 3 To finish up: -

* Open Startup Applications via the System > Preferences menu
* Click on 'Add'
* Enter 'Nvidia Settings' or similar for the name
* Enter 'nvidia-settings -l' for the command entry.

Now, upon reboot, your new effects will take place and should no-longer see any more of the annoying screen tear issue during videos, etc! Super thanks to kopiwe once again. This issue drove me mad! Once you noticed it the first time then you noticed it always.

Great South Run for Dizzy!!!!

2010-06-11T20:46:00.000+01:00

http://uk.virginmoneygiving.com/team/DizzyTeam I must be bonkers, but please sponsor Justin and I, it's for a good cause!!!!

Install Windows 7 from a USB Stick

2010-05-08T20:17:00.001+01:00

Thanks to the MaximumPC for the following article :

http://www.maximumpc.com/article/howtos/how_to_install_windows_7_beta_a_usb_key?page=0%2C0

Without which I would still have a dead laptop...

It's Aliveeeee!!!!!

2010-05-01T20:55:00.002+01:00

I'm back, Linux machine restored to full health. It wasn't the power supply directly but a dodgy fan causing it to overheat.

Linux Machine is dead.....

2010-04-02T09:37:00.001+01:00

Well I'm currently blogging from my old G5 iMac, the power supply in my PC is dead and will be until I can get some time to replace it.

Keep checking back for more posts.

Adobe Air and Tweetdeck in Mint 8 64bit

2010-01-08T15:58:00.001Z

Check out the post below. Finally got Tweetdeck and Air working under mint 8 64bit!!!!

http://www.htmlcenter.com/blog/tweetdeck-in-64-bit-linux/

Stop Seagate Drive from Going into STANDBY - Linux Mint 8 x64

2010-01-07T17:26:00.001Z

# sdparm -al /dev/sdd
    /dev/sdd: Seagate   FreeAgentDesktop  100D
    Direct access device specific parameters: WP=0  DPOFUA=0
Power condition [po] mode page:
  IDLE        0  [cha: n, def:  0, sav:  0]  Idle timer active
  STANDBY     1  [cha: y, def:  1, sav:  1]  Standby timer active
  ICT         0  [cha: n, def:  0, sav:  0]  Idle condition timer (100 ms)
  SCT       9000  [cha: y, def:9000, sav:9000]  Standby condition timer (100 ms)
# sdparm --clear STANDBY -6 /dev/sdd
    /dev/sdd: Seagate   FreeAgentDesktop  100D
# sdparm -al /dev/sdd
    /dev/sdd: Seagate   FreeAgentDesktop  100D
    Direct access device specific parameters: WP=0  DPOFUA=0
Power condition [po] mode page:
  IDLE        0  [cha: n, def:  0, sav:  0]  Idle timer active
  STANDBY     0  [cha: n, def:  1, sav:  0]  Standby timer active
  ICT         0  [cha: n, def:  0, sav:  0]  Idle condition timer (100 ms)
  SCT         0  [cha: n, def:9000, sav:  0]  Standby condition timer (100 ms)

Oracle Block Corruption

2010-01-05T14:10:00.000Z

Here is a great article on checking file headers within Oracle, it's proved useful for recovering deleted links to RAW devices!!

http://orainternals.wordpress.com/category/corruption/

Link above, article below:

June 18, 2009

Resolving corruption issue with file_hdrs dump

Filed under: Oracle database internals, corruption, recovery — orainternals @ 3:55 pm
Tags: controlf, dump, file_hdrs, ORA-01171, oradebug

One of our client had an interesting and bizarre corruption issue. Intermittently their database is corrupted.
ORA-01171: datafile 178 going offline due to error advancing checkpoint
ORA-01122: database file 178 failed verification check
ORA-01110: data file 178: ‘/app/u04/oradata/somedb/some_data_01.dbf’
ORA-01251: Unknown File Header Version read for file number 178
Error message printed above indicates that file header is corrupted. This is not a one time issue and recurring many times in the past 45 days or so. Database become unusable and only option was to restore the database from backup and recover it. A painful and business impacting issue. Client’s frustration is understandable.
Of course, Client tried normal channels to resolve this problem with out luck. Opening Service tickets with vendors, Relink software stack, update dbid, modify kernel parameters and replace hardware etc. Client has even planned to reinstall OS soon. Still, problem re-occurred every week. That’s when he reached out to us.
file_hdrs dump
Realizing that file header is corrupted, First thing, I wanted to do was that to find what exactly is there in those file headers. What type of corruption in those file headers? Is it a block formatted with null characters? or Is it that few fields are corrupted? This will give more clues and direct us in the right path. So, I asked the client to perform a file_hdrs dump when this problem re-occurs. Following commands were sent to the client.

oradebug setmypid
oradebug dump file_hdrs 10
exit

Above statement is to dump file headers at level 10. oradebug file_hdrs dump will print blocks from the file headers.

oradebug setmypid
oradebug dump controlf 10

Second dump (controlf dump) should print control file records to the trace file. Idea here is to match the file headers and control file file header section to see if we gain more insights in to this corruption issue.
It is quite possible that this could be a control file corruption and control file corruption can’t be ruled out yet. File headers and files can be corrupted. Essentially, this needs cross verification between control file and file headers to identify the root cause. At least, I was hopeful that this will point us in right direction.
dd of file header block
I also requested the client to take a backup of first few blocks of the corrupted file using ‘dd if=filename of=filehdr.out bs=8192 count=2′ command. In UNIX platform, this dd command will copy first two blocks (of block size 8K) in to a flat file. After every corruption, only workaround is to restore and recover the database and I wanted to collect as much information as possible in one round.
What happens on Friday?
Client also pointed out that this issue happens on Fridays only. Various groups were checking UNIX, SAN layers to see if there is anything special about Friday, looking for maintenance jobs that runs on Friday etc. Nothing of any significance shows up. At this point, we were waiting for the problem to reoccur.
And then it did…
file_hdr and controlf trace files
We received trace files from the client and reviewed it. We will concentrate on just one corrupted data file, even though 68 files were corrupted at this point.
control file section for that file printed below:

DATA FILE #32:
(name #41) /app/u04/oradata/somedb/somedata1.dbf
 creation size=12800 block size=8192 status=0x1c head=41 tail=41 dup=1
 tablespace 32, index=33 krfil=32 prev_file=0
 unrecoverable scn: 0x0000.00000000 01/01/1988 00:00:00
 Checkpoint cnt:48 scn: 0x0910.62fd2f34 05/08/2009 10:30:32
 Stop scn: 0x0910.6305098e 05/08/2009 17:42:13
 Creation Checkpointed at scn:  0x0000.000935a6 04/30/2009 21:42:29

Nothing jumps out. Checkpoint SCN is recent enough [ Of course, this problem happened in May 2009].
Let’s review the file header section for that corrupted file. Clearly , there is a corruption since controlf dump command itself is unable to print correct file header version.

File header version cannot be determined due to corruption <<<<
Dump may be suspect
 V10 STYLE FILE HEADER:
 Compatibility Vsn = 169870080=0xa200300
 Db ID=1755378070=0x68a0f196, Db Name='SOMEDB'
 Activation ID=0=0x0
 Control Seq=3032023=0x2e43d7, File size=401792=0x62180
 File Number=18, Blksiz=8192, File Type=3 DATA

If the file header is filled with null then above section starting with ‘V10 STYLE FILE HEADER:’ can not be printed. oradebug command is complaining that file header version can not be determined, while also printing fields from file header. Confusing and that doesn’t make sense: File header version is corrupt but fields from file headers can be printed. This means that we might need to review the output of dd command. But, before going that route , decided to compare corrupted file header output with another uncorrupted file in the control file trace file to see if we can spot any obvious issue(s).
controlf trace file for an uncorrupted file
Following first two sections prints the control file record section for a uncorrupted file. Checkpoint scn time line is matching for corrupted and uncorrupted data file records. This gives us a clue that control file record for these files may not be corrupted. Genuinely, there must be a corruption in the file header.

DATA FILE #33:
  (name #42) /app/u03/oradata/qnoldv01/ANOTHER_GOOD_FILE_01.dbf
creation size=12800 block size=8192 status=0xe head=42 tail=42 dup=1
 tablespace 33, index=34 krfil=33 prev_file=0
 unrecoverable scn: 0x0000.00000000 01/01/1988 00:00:00
 Checkpoint cnt:53 scn: 0x0910.641e926d 05/13/2009 16:25:26
 Stop scn: 0xffff.ffffffff 05/02/2009 13:41:42
 Creation Checkpointed at scn:  0x0000.000935c5 04/30/2009 21:42:31
 thread:1 rba:(0x3.e3bbd.10)

Let’s also review the file header section of an uncorrupted data file.

 Hot Backup end marker scn: 0x0000.00000000
 aux_file is NOT DEFINED
 V10 STYLE FILE HEADER:
 Compatibility Vsn = 169870080=0xa200300
 Db ID=1908337442=0x71beeb22, Db Name='SOMEDB'
 Activation ID=0=0x0
 Control Seq=34895=0x884f, File size=2434616=0x252638
 File Number=33, Blksiz=8192, File Type=3 DATA

Comparison of corrupted and uncorrupted file is not showing any insights either. OR Is it?
Not so fast…
There is a difference in the file header section between these these two file headers. Let me reprint both these file headers side-by-side to see if the difference can be spotted easily.
Corrupted file:

File header version cannot be determined due to corruption
Dump may be suspect
 V10 STYLE FILE HEADER:
 Compatibility Vsn = 169870080=0xa200300
 Db ID=1755378070=0x68a0f196, Db Name='SOMEDB'
 Activation ID=0=0x0
 Control Seq=3032023=0x2e43d7, File size=401792=0x62180
 File Number=18, Blksiz=8192, File Type=3 DATA

Uncorrupted file:

 Hot Backup end marker scn: 0x0000.00000000
 aux_file is NOT DEFINED
 V10 STYLE FILE HEADER:
 Compatibility Vsn = 169870080=0xa200300
 Db ID=1908337442=0x71beeb22, Db Name='SOMEDB'
 Activation ID=0=0x0
 Control Seq=34895=0x884f, File size=2434616=0x252638
 File Number=33, Blksiz=8192, File Type=3 DATA

Ahh.. Right there. DBID is different between these two files! How can the DBID be different in this situation? Client assured me that there is no transportable tablespace or read only tablespaces shared between databases going on here. How can the dbids different between two files in the same database? These tablespaces are both opened with read and write activity. We need to follow this clue.

Corrupted file:     :Db ID=1755378070=0x68a0f196 , Db Name='SOMEDB'
...
Uncorruped file     :Db ID=1908337442=0x71beeb22 , Db Name='SOMEDB'

After pointing out that dbid is different between uncorrupted and corrupted files, client dumped control files from other development and test databases to see if they can locate a db with dbid 1755378070. No databases had the same dbid.
Finally..
With dbid difference in mind, few hours later, client DBA recollected something. When they migrated from old database server to new database server, they used scp to move the database files from old server to new server. Of course, client DBA did not want scp connection to die when his VPN connection dies and so wrote a script to scp the files from cron entry as any good DBA will do.
After migration, system admins changed oracle password. Machine was supposed to be shutdown and kept in pristine condition for few weeks before returning the hardware. Unfortunately, it was not down.
I am sure, you figured out where I am going with it. There was a cron entry scheduled in that old DB server and that was quietly scp’ing the files from old database server to new database server corrupting the database. Client disabled that cron entry and also created new ssh key to avoid these issues.
I heard that client is able to enjoy his Fridays
This blog can be read in a traditional format resolving_corruption_issue_with_filehdr_dumps.
PS: Thanks to the client for allowing me to blog about this issue.

Convert .img to Virtualbox .vdi file

2009-12-31T19:35:00.001Z

To convert an .img file to the virtulbox .vdi format run the following:

VBoxManage convertdd  file.img file.vdi

VMWare modules on Mandriva 2010

2009-12-31T18:35:00.004Z

And here is a link for compiling VMWare modules on Mandriva. Trying out the new distribution and it's having issues with VMWare workstation.

http://communities.vmware.com/thread/203231

How to Join 2 avi files....

2009-10-11T23:36:00.000+01:00

Post borrowed from Linux Clues

http://linuxclues.blogspot.com/2008/08/mencoder-joining-two-avi-files.html

It is usual having an avi film split into two cdrom sized files of 700 megabytes each.

mencoder utility allows us to concatenate these two parts into a new reintegrate file.

mencoder (MPlayer's Movie Encoder) is a tool MPlayer provides to encode multimedia contents into files.
It supports among others, MPEG-4 video, libavcodec codecs, and PCM/MP3/VBRMP3 audio formats.
mencoder also possesses stream copying abilities and a powerful filter system (crop, expand, flip, ....).

So we have a film split into two files e.g: foo1.avi and foo2.avi, both with the same encoding characteristics (window size, codecs, bitrate...),

We execute this command that produces an output file called foo.avi which is the result of concatenating foo1.avi and foo2.avi files.
$mencoder -oac copy -ovc copy -forceidx foo1.avi foo2.avi -o foo.avi

The command options mean:
* -oac output audio codec
* -ovc output video codec
* -o output file name
* -forceidx forces creation of a new index.
copy means copying the original stream and do not change the codec it is encoded into (because of that it is very fast).

more info executing: $man mencoder

INSTALLING MENCODER

Ubuntu and Debian: $sudo aptitude install mencoder

VMware working on Jaunty!!

2009-10-03T11:24:00.000+01:00

After installing VMware from the .bundle you need to re-build the modules. This solution was taken from the following post :

http://ubuntuforums.org/showthread.php?t=1040351

I have the sollution for you.
First you got to remove the broken module:
sudo mv /usr/lib/vmware/modules/binary /usr/lib/vmware/modules/binary.old

then simply rebuild the module.
sudo vmware-modconfig --console --install-all

It should all work. If you have any problems let me know.

PS: Also you need the current headers for your kernel ofcourse and for obvious reasons the build-essential package to be able to build the modules.

Peace!

No more crackly sound in Linux!!!!

2009-10-03T10:56:00.000+01:00

This has been bugging me for ages, but after searching around google this morning I found the answer. Everytime I was booted into linux I used to get a crackling or hissing noise coming from the speakers constantly, after much searching I've found the solution. For my soundcard (HDA Intel Nvidia chipset) the culprit was the Analog Mix channel. In the volume control->preferences I enabled the channel so I could control the volume, then muted the channel. Hey presto, no more crackling!!!! Google is King!!!!

Extract Data from Excel using VBScript

2009-09-03T16:51:00.001+01:00

Another job for this afternoon. How to extract all the data from an Excel Workbook not using .csv’s. Again, thanks to another website (Google is king!!!) the following link helped:

http://www.greghatcher.com/apers/VBScript/ExcelExtractScript.aspx

SQl Server Reporting Services

2009-09-03T14:42:00.001+01:00

Who said SQL Server 2005 was going to be easy???? After a “simple” install of reporting services I could not get the damn thing to work. After much searching of google,msdn etc, etc, etc I found the following info on another Blog (Thanks Rob)

http://lumbgaps.blogspot.com/2007/10/sql-2005-reporting-services.html