Wednesday, February 22, 2012
Posted by admin on November 28, 2010
The Cisco IOS command line, like that of Linux and MS-DOS command line editors, features a number of built-in editing commands to enable movement around the command line and command history buffer. WAIT! There is more to read… read on »
Posted by admin on February 28, 2010
Although it doesn’t have the sophistication of the Cisco IOS keyboard shortcuts or the Linux command line editor, the MS-DOS shell in Windows Server, XP and Vista does have command line editing and allows the easy recall and modification of previous commands. WAIT! There is more to read… read on »
Posted by admin on November 28, 2009
On Linux, TAR is a general purpose backup and archive tool. Here you’ll find five common TAR uses with examples. WAIT! There is more to read… read on »
Posted by admin on February 14, 2009
When Google displays the results to searches, the heading shown for each site is taken from the title tag of the web pages listed.
By default, Blogger page titles have the form Blog Title + Post Title.
When displayed in search engine results, the blog site name will thus be displayed first.If your blog title is not directly relevant to their search, your blog may then be overlooked.
This simple trick reverses the title so the post name is shown first followed by the blog name making it more likely visitors scanning search results will click through onto your post.
To change the page title to Post Title + Blog Title change find the line:
<title><data:blog.pageTitle/></title>
In the site template (this is edited by clicking on Layout / Edit HTML (note: as with any template changes you should back up your template before making any changes).
Change this text to:
<b:if cond='data:blog.pageType == "index"'><title><data:blog.pageTitle/></title><b:else/>title><data:blog.pageName/> : <data:blog.title/></title></b:if>
In a nutshell, this tells Blogger to leave the page title as is if the page is the home page leave the title
as is; if it’s a post page however change the title as described above.
Posted by admin on September 28, 2008
Status codes returned by FTP servers. WAIT! There is more to read… read on »
Posted by admin on June 21, 2007
1. Power-On Self Test – POST
This is a hardware driven process that the PC will go through. This entails performing various hardware checks – memory, disk etc – and carrying out instructions contained within the system BIOS. Failure at this point will either result in an on-screen diagnostic message or a series of beeps; the number of beeps indicating the nature of the problem. Refer to the BIOS manufacturer for further details. See also: PC boot process.
2. Inital start-up Phase
In this stage of start-up, the settings in CMOS memory are used to determine from where and how the system will load its operating system, notably the storage devices present and boot order. Typically this will be floppy disk, hard disk or CD-ROM although it can also include network adaptors and SCSI controllers.
When the system is to load from is a hard disk – such as when no floppy disk is present – the first sector of the hard disk is loaded. This is known as the Master Boot Record – MBR – and contains a sequence of code and a table of four entries defining the locations on the hard disk of the primary partitions (known as the partition table).
Once loaded, the code from the MBR is used to scan the partition table and find the location of the Active Partition, load the first sector – the boot sector - of this partition and then pass control to it. The code in the boot sector is very small and provides only enough information to understand the partition format sufficiently enough to load a few other files – notably NTLDR – and just from the root of the partition. It now loads NTLDR, the BIOS portion of the boot process finishes and the code in NTLDR takes over.
From this list, it’s obvious that there are several vital elements that must be present for NT, 2000 and XP to load:
3. Boot Loader Phase
Once NTLDR is in control it starts the process of loading NT/2000 or XP. This includes:
[boot loader] timeout=10 default=multi(0)disk(0)rdisk(0)partition(1)\WINNT [operating systems] multi(0)disk(0)rdisk(0)partition(1)\WINNT="Microsoft Windows 2000 Professional" /fastdetect
This shows that the system is to be loaded from the director \WINNT on partition 1 of hard disk 0 and its title is Windows 2000 Professional.
NTDLR now loads Ntdetect.com from the root of the boot partition and runs it. This shows a message on screen (in NT and 2000) to the effect ‘NT Detect: checking hardware’ and scans for basic system hardware such as system clock, mouse and keyboard, video adaptors and disks. Ntdetect next passes details of the hardware it has found back to NTLDR. In NT and 20000, this now displays the on-screen message ‘OSLOADER V4.0′, before structuring and organising the information returned by ntdetect.com. It then loads the hardware extraction layer into memory before loading and finally passing control to ntoskrnl.exe, found in systemroot\system32.
The core of operating system is now loaded and established. This includes:
ntoskrnl.exe loads the file systemroot\system32\config\system, builds the registry key HKEY_LOCAL_MACHINE\SYSTEM and reads the information from it. Under this key are various subkeys including Last Known Good, Failed and Default subkeys (later on in the boot process one of these keys can be selected). The kernel then uses information previously returned by ntdetect.com to build HKEY_LOCAL_MACHINE\HARDWARE which contains details of the various hardware and resources to be allocated. As the kernel loads, Windows 2000/XP displays the Start Up progress indicator bar along the bottom of screen.
Once the hardware is up and running the kernel then loads, and if necessary starts, various system services defined in HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\servicename.
After this the kernel initiates the session manager (smss.exe) which assigns environmental variables, switches from text to graphics mode, starts the logon manager – winlogon.exe – and creates virtual memory page files.
The start-up process is very nearly complete.
In this final stage, the services subsystem (SCM) and local security authority (LSA) are loaded and the system waits for the CTRL+ALT+DEL key combination. After CTRL+ALT+DEL is detected, the system collects the username and password and sends the information to LSA for authorisation. If authorisation is granted, SCM starts auto-load drivers while winlogin starts up.
After successful login, the Last Known Good registry settings are updated to reflect the current registry; group policy objects are applied and start-up programs run.
Posted by admin on November 28, 2006
A quick and dirty port scanner in Perl. WAIT! There is more to read… read on »
