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Linux / UNIX File Formats

DenyHosts: Remove / Delete an IP address

I've followed your guide and installed denyhosts to protect on my RedHat 5.3 OpenSSH based server. However, I've been accidentally blocked out from my home ADSL IP address. I tried removing my blocked IP from /etc/hosts.deny, but it did blocked it again quickly. It appears that DenyHosts keeps track of the attempts somewhere on disk or memory. How do I remove my own home IP address from DenyHosts?
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Ubuntu Linux: Firefox and Desktop Application Fix Smooth Font Problem ( Render Font Correctly )

Q. How do I render font smoothly in Ubuntu Linux / Gnome desktop systems? How do I get look a likes of the Microsoft / Mac OS X smooth fonts for Firefox and other applications?
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Linux: Find Out If a Particular Driver / Feature Compiled Into Running Kernel or Not

Q. I know how to find out information about compiled driver under FreeBSD kernel. But, how do I find out if a Particular feature, driver or filesystem support is compiled into my running Linux kernel or not? How do I find out if DMA support is compiled into my kernel?
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How To Select Best Linux Desktop Application

Q. I'm new to GNU/Linux world and a single query (apt-cache search office or yum search 'office') shows so many application for a single task such as network monitoring or office applications. The number of apps choices just confusing. How do you select application from so many choices?
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FreeBSD csh / tcsh: Export Shell Variable

Q. I'm using FreeBSD 7 with csh (tcsh) shell. How do I export shell variable under FreeBSD operating systems?
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pdfimages: Extract and Save Images From A Portable Document Format ( PDF ) File

Q. How do I extract images from a PDF file under Linux / UNIX shell account?
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BASH: Prepend A Text / Lines To a File

Q. I can append text to a file using >> operator but how do I prepend a text to a file? I want the opposit of >> operation?
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psql: FATAL: Ident authentication failed for user "username" Error and Solution

Q. I've installed Postgresql under Red Hat Enterprise Linux 5.x server. I've created username / password and database. But when I try to connect it via PHP or psql using following syntax:

psql -d myDb -U username -W

It gives me an error that read as follows:

psql: FATAL: Ident authentication failed for user "username"

How do I fix this error?
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Red Hat Linux Static Routing Configuration

Q. I've two network interface connected to two different routers as follows:
[a] eth0 LAN network - gateway IP -

[b] eth1 ISP assigned network - gateway IP -

I can only ping to public server but not to another servers inside LAN? I'm not able to route traffic via How do I configure static routing under Red Hat Enterprise Linux 5.x or CentOS Linux 5.2?
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Ubuntu Linux Disable control-alt-delete [CTRL-ALT-DEL] Emergency Keypress Handling

Q. How do I delete control-alt-delete emergency keypress handling to improve security of my Ubuntu Linux server?
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