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Showing posts from May, 2013

Tutorial on Vlookup function for Excel

A quick notes on Vlookup Excel formula.

Vlookup formula is quite useful to find and locate data on Excel.

Table below will be used on how to demonstrate and use vlookup. But this basic idea is the same way you can apply even on a complicated or huge amount of excel data.

First we examine the parameters of Vlookup.

By typing Vlookup formula on Excel, Excel will prompt or display the parameters needed to complete the function.

Let's try to simplify or use lay man terms for the vlookup parameters.

In Excel 2007 that I'm using it displays these parameters below when I type Vlookup formula :

=Vlookup (look_up_value, table_array,col_index_num, [range_lookup])

The look_up_value is indeed the value that you're looking for or the data you're trying to find.

The table_array is the range of cells, or basically the whole cells or columns in which the data will be search.

The col_index_num, is the data that will be returned once the look_up_value matches any data define on th…

Launch Program with Admin Privileges using an elevated command prompt

Running Control Panel Applets with administrative privileges.
A quick notes on how to launch a control panel applet from a user with no Admin rights. Elevated command prompt, is running the command prompt with Administrative privileges.
In an Active Directory environment, it's quite a bad idea giving Domain Admin rights to any users or setting the domain user  account as a member of Local Administrator.
Why it is a bad idea? I guess  you know the downside of it.
Troubleshooting or doing some simple tasks  on AD  or domain environment, is quite a hassle.  If the active or current user does not have an Administrative privileges.
I bet if you like to do things, like installing or removing programs. It would be better if you will login with Administrator account, in such a way you can do things smoothly.
If you're not login as an Administrator then you have to bear the annoying pop up box that keep asking for an Admin password.
Well, of course there are a lot of ways to uninstall…

How DHCP works?

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A quick notes on how DHCP process works. DHCP - an acronym for Dynamic Host Configuration Protocol

DHCP is one of the most important thing in a network infrastructure.
Why it is most important? Would you link to configure 30 or more computers with an static IP?

Or would you prefer,  just plugging  a network cable and that's it DHCP will do the rest.
If DHCP works as cool as that, why bother how it works on the background?
It's good to know how things works on the background, not just because you're preparing for some certification and you got to nail down that cert.

It still a very good thing to know how things are being done on the background.
Download Network Monitor Tools from Microsoft site on this link below:

http://www.microsoft.com/en-sg/download/details.aspx?id=4865

On start page of Network Monitor, click the Network Interface on which the packet will be sniff.

If the PC has only 1 NIC, it will be check by default. If PC has multiple NICs check the desired NIC.



Cli…

Basic Linux File Permissions

A good start in learning Linux is to understand how to setup file permissions.
Linux has this permissions: "No Access" or "No Permissions", "Execute" only, "Write" only, "Write and Execute", "Read" only, "Read and Execute", "Read and Write", and of course "Full Access" or "RWX"

Below is a table that lists on how permissions is being derive.
Permissions is converted from Octal to Decimal.

4 2 1 Equivalent Access RightEquivalent Decimal ValueWhy?000No Access (zero)0Zero001X (execute)10+0+1=1010W (write)20+1+0=2011W+X30+1+1=3100R (read)41+0+0=4101R+X51+0+1=5110R+W61+1+0=6111RWX (Full Rights)71+1+1=7
From the table above we can come up with this summary:

0 is no permissions, 1 is execute only, 2 is write only, 3 is write and execute, 4 is read only, 5 is read an execute, 6 is read and write and 7 is full access which hackers want to have.

To set file permissions we can use a "chmod&quo…