Linux LVM: Recovering a lost volume.

This is one of the best "How To" to recover an lost LVM, it works forme me ;)

.."NOTE: Do not attempt these steps unless you have a firm understanding of UNIX / LINUX.  The concepts here are relatively advanced."....

The Perfect Server - CentOS 5.7
http://www.howtoforge.com/perfect-server-centos-5.7-x86_64-ispconfig-2

"This tutorial shows how to set up a CentOS 5.7 server (x86_64) that offers all services needed by ISPs and web hosters: Apache web server (SSL-capable), Postfix mail server with SMTP-AUTH and TLS, BIND DNS server, Proftpd FTP server, MySQL server, Dovecot POP3/IMAP, Quota, Firewall, etc."

Linux Fundamentals, Part 1 

DIY: Destroy data on drives via a Linux live distro

http://www.techrepublic.com/blog/doityourself-it-guy/diy-destroy-data-on-drives-via-a-linux-live-distro/835

How to lock down Linux

"Any operating system can be cracked if you don’t adequately protect it. Yes, even Linux. Here are some security basics on how to protect your Linux systems."

Dig Howto

Instead using nslookup use dig,  in RHEL distro, dig is part of bind-utils package.
http://www.madboa.com/geek/dig/

How to SMTP Auth in Sendmail (CentOS)

By default sendmail-cf  is not installed in CentOS:

yum install sendmail-cf

Then edit /etc/mail/sendmail.mc and add this:

TRUST_AUTH_MECH(`EXTERNAL DIGEST-MD5 CRAM-MD5 LOGIN PLAIN')dnl
define(`confAUTH_MECHANISMS', `EXTERNAL GSSAPI DIGEST-MD5 CRAM-MD5 LOGIN PLAIN')dnl

compile the new configuration:

make -C /etc/mail/

saslauthd must by running:

/etc/init.d/saslauthd start 

and make it available on startup:

chkconfig  saslauthd on

then restart sendmail:

/etc/init.d/sendmail restart

and it's ready to use
For a powerful mail server, you can combine this configuration with MailScanner, clamav and grey-list.

Risk Management Strategy for the Provide Domain Name Resolution Services Critical Function

http://www.dhs.gov/xlibrary/assets/it-sector-risk-management-strategy-domain-name-resolution-services-june2011.pdf

Unix file compression utilities

to compress and zip:

tar -czvf archive.tgz files/

 more info

http://www.fluidthoughts.com/howto/tar-gzip/

Virtualization in Linux, KVM way by IBM

Well documented information at:
http://publib.boulder.ibm.com/infocenter/lnxinfo/v3r0m0/index.jsp?topic=/liaat/liaatkvm.htm&sf1617284=1

vi intro -- the cheat sheet method by Daniel Robbins

vi,  useful  cheat sheet
http://www.ibm.com/developerworks/linux/tutorials/l-vi/

How to add rpmforge repo to CentOS 5.5

x86_64 version

 wget http://dag.wieers.com/rpm/packages/rpmforge-release/rpmforge-release-0.3.6-1.el5.rf.x86_64.rpm

rpm -ivh rpmforge-release-0.3.6-1.el5.rf.x86_64.rpm

You can disable the rpmforge repo in /etc/yum.repos.d/rpmforge.repo
and changed enabled = 1 to enabled = 0

Source

http://blog.bloke.com/2010/05/enable-rpmforge-for-centos-5-5-for-subversion-1-6/

Updating time on Linux

First install NTP
yum install ntp
 then update by a remote NTP server
ntpdate my.server.xx

or set manually
date mmddHHMM[YYyy]